CN1976749A - Nonwoven composites and related products and methods - Google Patents

Abstract

The present invention in certain embodiments is directed to a catalytic substrate suitable for use in a number of applications, including as a substrate in a catalytic converter. Another aspect of the present invention is a filtering substrate suitable for use in a number of applications, including as a substrate in a particulate filter, such as a diesel particulate filter (DPF), or diesel particulate trap (DPT). The invention also provides an improved substrate for removing and/or eliminating pollutants from the exhaust of combustion engines. The catalytic substrate and filtering substrate provide, in certain embodiments, improvements in removing pollutants from an exhaust gas. The improvements include one or more of the following: faster light-off period, depth filtration of PM, less backpressure, lower probability of clogging, ability to be placed in multiple locations in the exhaust system including the manifold or the head itself, high probability of catalytic reaction, high conversion ratios of NOx, HC, and CO, a faster burnoff of PM, minimization of catalyst material use, and the like.

Description

Non-woven composite and Related product and method

Technical field

The base material that the present invention relates to be applicable to the specific reaction of catalysis and be applicable to filter particulate material, and relate to associated specific embodiments, such as but not limited to the emission of handling internal combustion engine, relate more specifically to be applicable to catalyst/substrate combination and the Related product and the manufacture method of emission control and correlated process.Believe that embodiment of the present invention described herein is by helping to recover or safeguarding the natural key element that earns a bare living (comprising air, water and/or soil) that one or more are basic and improve the quality of environment for human survival significantly.The present invention and embodiment thereof are more fully described at summary of the invention with in describing in detail partly in the back.

Waste gas, industry and pollution

Engine produces many power and the mechanical power that use in the whole world.Internal combustion engine perhaps is the device the most widely that distributes, because it is more effective than those external-combustion engines that exist on for example old-fashioned train of external-combustion engine and the steamer.In internal combustion engine, the burning of fuel is carried out in inside.This engine produces motion and the power that is used for many purposes.Example comprises motor vehicles, locomotive, boats and ships, RV, tractor, construction equipment, generator, power plant, manufacturing facility and industrial equipment.Be used for providing the fuel of power to include but not limited to gasoline, Compressed Gas, diesel oil, ethanol and vegetable oil to internal combustion engine.Engine mechanical and be used for to its provide power fuel intrinsic poor efficiency cause giving off many pollutants.Therefore, though they bring great innovation and facility, millions of engines of whole world use are at present signifying sizable air pollution source.

Internal combustion engine produces the pollutant of two kinds of main types: particle and non-particulate thing.It generally is little solid and liquid particle that particle pollutes.Example comprises carbonaceous flue dust, dust and other associated particulate.Non-particulate pollutant comprises gas and little molecule, for example carbon monoxide, nitrogen oxide, sulfur oxide, unburned hydrocarbon and VOC.Particulate pollutant can leach from waste gas, can further burn in some cases.Make non-particulate pollutant change into the uncontamination thing.For example " " chemical reaction and fugitive emission also can produce this two pollutant to tail gas in non-engine source.

Air pollution can be given human and environment causes serious health problem.Ground level ozone and airborne particulates are this country causes one of biggest threat to human health two pollutants.Ozone (O ₃) can stimulate respiratory system, cause cough, have sore throat and/or the interior burning heat sensation of respiratory tract.Ozone is one of reason that forms smog.Ozone can also weaken PFT, cause uncomfortable in chest, pant and Tachypneic sensation, and can increase the weight of asthma.Particle contamination is made up of small solid or drop, and they are enough little gos deep in the lung with activation and cause serious health problem.When being exposed among these granules, people can feel nose and throat irritation, injury of lungs and bronchitis, and can increase people's heart or the ill danger of lungs.The short-term effect of air pollutants comprises exciting eye, nose and larynx.Also can cause the infection of the upper respiratory tract such as bronchitis and pneumonia.Other symptom can comprise headache, feel sick and allergic reaction.The long-term health influence can comprise chronic respiratory disease, lung cancer, heart disease, even infringement brain, nerve, liver or kidney.Continue to be exposed to the lungs that influence the growth children in the air pollutants, the elderly's medical condition is worsened or complicate.

The medical condition that is caused by air pollution can be very expensive.The health care cost, at the annual cost of the influence multi-million dollar of workplace forfeiture production capacity and human welfare.The understanding pollution is to health affected and find improvement, prevent or the means of pollution abatement will not only improve all the people's overall respiratory health, and will reduce material burden and cost that the health care system is brought.

For this reason, government, environment mechanism and various industry have been responsible for reducing the air pollution level of emitting from various sources.Government organs are regulated discharge standard and the main body of implementing regulations.At European Union (EU), regulations come from the rules of the European Community; Each member state carries out these regulations.For example, most of EU state is to producing the source taxation of too much air-polluting.New development is Kyodo Protocol (Kyoto Protocol), advocates the whole world and reduces greenhouse gases.Many countries comprise that EU has approved this agreement.European Union, Japan and the U.S. have issued some standards that the whole world is the strictest, but other many countries comprise that Argentina, Brazil, Mexico, Korea S, Thailand, India, Singapore and Australia have all issued about the air-polluting regulations.In the U.S., there are a lot of different groups to influence the regulations of certain areas, for example: state environment mechanism (as the California air resource committee (CARB)), national park, forest mechanism and mine safety health control department.Some states and the metropolitan area that do not reach NAAQS (NAAQS) are decided to be " non-attainment area ", carry out themselves standard.CARB is one of the strictest mechanism of U.S.'s air pollution management in history always.But chief U.S. management organization is Bureau for Environmental Protection (EPA).It is created the correction in the air cleaning decree (CAA) in 1963 in 1970 by Nixon government.The air cleaning decree is comprehensive federal law, and the area of its management, air fixing and mobile pollution source discharge.(referring to the 42U.S.C.SS 7401 of for example air cleaning decree and following or the like (1970)).Through five big corrections, the last time is in nineteen ninety to the air cleaning decree.Nineteen ninety the correction major part of air cleaning decree is intended to tackle do not relate to or relate to not enough problem such as acid rain, ground level ozone, stratospheric ozone is exhausted and the air poisonous substance.These corrections require 175 new regulations of EPA distribution, the use etc. that comprises vehicular discharge, gasoline reform, exhausts the chemicals of ozone.

According to air cleaning decree rules, EPA formulates the regulations of the pollutant that maybe may be pernicious to people of being pernicious to people.This cover " index pollutant " comprising: (1) ozone (O ₃); (2) plumbous (Pb); (3) nitrogen dioxide (NO ₂); (4) carbon monoxide (CO); (5) particle (PM); (6) sulfur dioxide (SO ₂).Every kind of index pollutant is described successively.

In the U.S., ground level ozone (main component of smog) remains pollution problem.Ozone directly is not disposed in the air, but the reaction in the presence of heat and sunlight of VOC (VOCs) or reactive organic gas (ROGs) and nitrogen oxide (NOx) generates ozone.Comprise combustion fuel from many sources and emit VOCs/ROGs from solvent, PETROLEUM PROCESSING and agricultural chemicals, they are from the source such as motor vehicles, chemical plant, refinery, manufactory, consumer and commodity and other industrial source.Motor vehicles, power plant and other Combustion Source are emitted nitrogen oxide.Ozone and ozoniferous precursor pollutant also can be carried several miles from its source by wind.1997, EPA revised the NAAQS about ozone, replaced 1 hour ozone 0.12ppm standard with new 8 hours 0.08 PPM (ppm) standards.

Nitrogen dioxide (NO ₂) be to pass through the reactant gas that oxidization of nitric oxide (NO) generates.(this term is used to describe NO, NO to nitrogen oxide (NOx) ₂With other nitrogen oxide) in forming ozone and smog, play a major role.The people comprises the high-temp combustion process for the main source of NOx discharging, as those high-temp combustion processes that take place in automobile, heavy construction equipment and the power plant.Family heater and gas burner also produce quite a large amount of NO ₂

Carbon monoxide (CO) is a kind of colourless, tasteless toxic gas, can generate by the imperfect combustion of carbon in the fuel.In the U.S., motor vehicles waste gas accounts for about 60% of CO discharging.In the city, may be up to 95% CO discharging from automobile exhaust gas.Other CO emission source comprises industrial process, the burning of non-transport fuel and natural pollution source such as phosphorescent light.

Particle (PM) is the term that is used for describing the mixture of solids that air finds and drop.Some particles are enough big or black, can cigarette ash or the smog form see.Other particle is very little, can only detect with electron microscope.These particles in very wide particle size range (" carefully " grain diameter less than 2.5 μ m than coarse grain greater than 2.5 μ m) come from many different fixing and mobile pollution source and natural pollution sources.Particulate (PM-2.5) is by producing from motor vehicles, generating and industrial plants and from the fuel combustion of dwelling house fireplace and timber stove.Coarse grain (PM-10) generally is that the source from vehicle, material processing apparatuses, pulverizing and grinding operation that travels such as dirt road and wind dust emits.Some particles are directly originated as emitting chimney and the automobile from it.Under the certain situation, such as oxysulfide, SO ₂, the gas of NOx and VOC and airborne other compound interact and form particulate.Their chemistry and physical composition change along with place, season and weather.1997, EPA increased by two new PM-2.5 standards, with year and 24 hours standard be decided to be 15 microgram/cubic meters (μ GA) and 65 μ g/m respectively.

Can generate sulfur dioxide during sulfurous fuels (as coal and oil) burning, for example in Metal Melting and other industrial process.

Last a kind of index pollutant lead is in history because of using leaded fuel to produce in the automobile.Because of reducing the management effort of Pb content in the gasoline, in the past decade the influence from transportation department descends.At present, metal processing is the main source of discharging Pb in atmosphere.

The air cleaning decree requires EPA and each state to draft the plan of the NAAQS that satisfies these six kinds of index pollutants.Outside these six kinds 188 kinds " poisonous air pollutants " of listing separately.The example of poisonous air pollutants comprises benzene, exists in gasoline; Perchloroethylene is discharged from some dry-cleaning equipments; And carrene, be used as solvent and paint stripper in many industry.Some airborne poisonous substances are discharged by natural pollution source, but great majority come from artificial source, comprise mobile pollution source (for example automobile, truck and bus) and stationary source (for example factory, refinery and power plant).CAA requires EPA that these 188 kinds of pollutants are drafted the planning of carrying out in two stages.Phase I is by the source of differentiating toxic pollutant and draft the technical standard that reduces these pollution sources effectively and constitute.EPA has determined to surpass the list of 900 kinds of stationary sources, this causes new airborne toxic emission standard, have influence on many industrial source, comprise: chemical plant, oil plant, Aero-Space manufactory and steel mill, and less source, as drycleaner's, commercial sterilisation device, secondary lead smelting furnace and electrodeposited chromium equipment.Second stage is by estimating residue danger and guaranteeing that overall planning has reached substantive strategy and the program polluted of reducing and constituted; This stage is still underway.

Internal combustion engine directly is subjected to the influence of these regulations, because their discharge index pollutants.These engines rely on two kinds of fuels run.The most frequently used fuel is gasoline and diesel oil.Every kind of fuel all comprises the complex mixture of hydrocarbon compound and many other materials of trace comprise sulphur.Even when completing combustion, these fuel also produce pollutant.In addition, because engine can not " safety " burn some fuel incomplete oxidation, thereby the additional pollutant of generation.Also can use the fuel of other type, for example alcohol mixture, vegetable oil and other fuel known in the art.

In petrol engine, for reducing discharging, the Hyundai Motor engine is carefully controlled the amount of burnt fuel.Make great efforts to keep air-fuel ratio very near stoichiometric point, stoichiometric point is the desirable air-fuel ratio of calculating.In theory, all fuel of oxygen combustion in will be under this ratio with air.In the driving procedure fuel mixture in fact therewith desired proportions considerable difference is arranged.Sometimes mixture may rare (for example air-fuel ratio is higher than 14.7 representative value), mixture possibility dense (for example air-fuel ratio is lower than 14.7) sometimes.These deviations produce various air dischargings.

The main emission of gasoline automobile engine comprises: nitrogen (N ₂) (air is 78%N ₂); Carbon dioxide (CO ₂), combustion product; And steam (H ₂O), another kind of combustion product.These emissions (but are generally believed CO in the atmosphere to the mankind are harmless mostly ₂Excessive is the factor of facilitating global warming).But petrol engine also produces carbon monoxide, nitrogen oxide and unburned hydrocarbon, and these are included in (unburned hydrocarbon constitutes the part that ozone forms mechanism with NOx) in the index pollutant of EPA.

Diesel engine also produces the index pollutant.These engines utilize hydrocarbon-fraction, and hydrocarbon-fraction is fully lighted a fire during compression in the presence of oxygen automatically.Usually, diesel oil burns in cylinder combustion and produces than the more substantial particle of gasoline and pollutant nitrogen and sulfur oxide (being respectively NOx and SOx).Even so, diesel fuel mixtures is rare usually, has the oxygen than substantial amount.Therefore, more complete usually than the burning of the hydrocarbon of short chain, produce than gasoline carbon monoxide still less.Than the more difficult completing combustion of the hydrocarbon of long-chain, can cause generating particle residue as " carbon black ".

Although there are these defectives, fossil fuel enrich, are easy to handle and be economical.Therefore, these fuel will be represented the main source of machine power and pollution over the next several years.In addition, the generality of internal combustion engine has illustrated that fossil fuel will be the reasons of the energy of necessity.

Produce main air-polluting internal combustion engine at least three markets arranged: 1) road engine, equipment and the vehicles of Yi Donging, 2) mobile non-road engine, equipment and the vehicles and 3) fixing or " point " pollution sources.In each of these markets, government organs and other are organized and have all been instructed the limit air level of pollution.Along with the quantity of the internal combustion engine that uses increase sharply and also injury that air pollution is brought solve manyly, it is strict further that these restrictions have become.Become tight regulations day by day and required industry constantly to study, develop and invest in new emission control technique, from the fuel formulation to the engine, newly design, to after-treatment device.The validity of these technology is all different with cost, makes abidance by rules institute of company requisite but become.Single emission control technique can not remove still that all are contaminants associated, so often must multiple technologies use together so that the vehicles of particular type or equipment can satisfy the emission limit set of stipulating.Describe in these markets, its regulations and the technology paragraph afterwards that relied on thereof.Describe described technology in more detail in this section, comprise its pluses and minuses.Though these parts focus on engine, equipment and the vehicles of the U.S., also there are similar products like and regulations in other area.For example, EU has similar market size, recycle more than waste gas but concentrate on SCR as Exhaust Control for Diesel Engine technology EU, EU uses catalytic converter in the little cross-country engine of larger proportion, and the ratio of Diesel engine is much bigger in light vehicle.There is its oneself the peculiar difference that is different from the U.S. in other area, but uses the air pollutants of the equipment and the restriction same type of same type basically.

Movably road engine, equipment and the vehicles include but not limited to passenger vehicle, light-duty cargo truck, small-sized passenger-cargo carriage, SUV (SUVs), bus, van, small truck, motor bus and are designed for two-wheeled or motor tricycle on the road.Always as the typical case, the present air pollutants according to the rules more regulations of substandard are continued so aspect emission control in these markets.

Automobile and Truck Market are divided by weight.The following vehicle of 8,500 pounds of gross vehicle weight ratings (GVWR) is considered as light vehicle.Be designed for carrying 8,500lbs GVWR and 10, the vehicle between the 000lbs GVWR is considered as medium sized vehicle.Be not be designed for manned purposes surpass 8, the vehicle of 500lbs GVWR is a heavy vehicle.

Passenger vehicle and light vehicle were pressed car weight and fuel type management in the past, but will be them one group of management in the standard in the future.Be lower than 1% in about 1,700 ten thousand new passenger vehicles produced in USA and the light vehicle and use Diesel engine.Passenger vehicle and light vehicle comprise those vehicles such as manufacturer's manufacturing of Ford, GeneralMotors (GM), DaimlerChrysler, BMW, Honda, Hyundai, Daewoo, First Automobile Group, Toyota, Nissan, SAIC-Chevy and Subaru.

There have been decades in regulations to passenger vehicle and light vehicle, but become much strict recently.From Tier 2 standards that (MY) the 2004-2009 stage in vehicle year progressively adopts, require Original equipment manufacturers (OEMs) to guarantee that its automobile reaches certain standard and keeps the population mean level of NOx discharging.By 2007 6, the following vehicle of 000lbs GVWR must meet standard fully, and 6,000-8, the vehicle of 500lbs and must meet standard in MDVs to 2009 year.Included pollutant comprises in Tier 2 standards: NOx, formaldehyde (HCHO), CO, PM and non-methane organic gas.Always there are the regulations tighter than EPA the California, other state comprise New Jersey, New York, Vermont, Myanmar because of and the Massachusetts added the California to new old vehicle than the low emission standard.The manufacturer that does not meet described standard forbids producing its vehicle in these markets basically, and that finds on market will impose a fine.In the component market, each state is by the discharging of Check and Maintenance (I/M) program management automobile and light vehicle.These programs are often created by the state executive plan (SIPs) that the below standard zone of National Environmental air quality (NAAQ) requires.Satisfy new car and component market standard-required simultaneously and adopt emission control technique, normally parallel.

In history, triple effect catalytic converter generally uses in automobile and light vehicle.Recently to the improvement of these converters (as the porosity that improves base material, optimize wash coat, reduce catalyst load etc.) emission control is improved gradually.For meeting U.S.'s regulations of latest edition, manufacturer may increase the catalyst load or the base material quantity of per car.The automobile that does not meet in the use of inspection/maintenance standard must be changed imperfect technology or buy attachment device.Other emission control system includes but not limited to advanced spraying system (as injection timing, expulsion pressure, velocity mode (rate shaping), common rail injection and Electronic Control), the Combustion chamber design (as higher compression ratio, piston-shaped and nozzle location), variable valve timing, catalytic converter and the filter that change.

Heavy vehicle (HDV) comprises 8, individual and commercial truck and bus that 500lbs GVWR is above.The most diesel fuels that rely on of these engines turn round; Produce more than 300,000 every year in the U.S..Manufacturer and engine supplier include but not limited to Cummins, Caterpillar, Detroit Diesel, GM, Mack/Volvo, Intemational/Navistar, Sterling, Western Star, Kenworth and Peterbilt.For providing other company of other emission control technique, the component market includes but not limited to Donaldson, Engelhard, Johnson Matthey, Lubrizol, Fleetguard, Cleaire, Clean Air Partners and Engine Control Systems.

Heavy truck is just facing to the reduction discharge standard of the strictness of PM, NOx, CO and non-methane hydrocarbon (NMHC).The PM standard came into force in 2007, and NOx and NMHC standard progressively adopted from the 2007-2010 stage.Similar with light vehicle, California and some other state and metropolitan area are often formulated the discharge standard tighter than EPA.Non-compliant vehicle forbids that manufacturer sells.What do not meet the NOx standard makes great efforts the highest per car fine $12,000 according to size and improvement.Though other industry such as locomotive, boats and ships, agricultural and building industry also use with heavy vehicle in the very similar engine of engine, the HDV market plane is to strict emission control standards.Simultaneously, some states and metropolitan area (as California, New York and Seattle) require extra improvement or excitation to improve with further reduction pollution level.There is the technology that meets approved level and condition through identifying in these areas.Example comprises the diesel oxidation catalyst of the diesel oxidation catalyst silencer of Donaldson and diesel particulate filter, Cleaire and diesel particulate filter, and the cyclic regeneration technology particulate filter of Johnson Matthey.

Include but not limited to advanced spraying system (injection timing for meeting the emission control technique that these standards and improvement adopt, expulsion pressure, velocity mode, common rail injection and Electronic Control), waste gas recirculation, the change of Combustion chamber design (higher compression ratio, piston-shaped and nozzle location), advanced turbocharging, ACERT, diesel particulate filter, the NOx absorber, SCR, conventional catalytic converter, catalytic exhaust gas silencer and diesel oxidation catalyst.Begun many in these emission control technique are are newly researched and developed for meeting standard in 2007.For the emission control solution of determining 2007 HDVs has been paid huge cost and effort.

Motorcycle is another kind of mobile road traffic instrument, comprises being designed for two-wheeled and the motor tricycle that road uses.Motorcycle mainly uses Fuel Petroleum.Manufacturer includes but not limited to: Harley Davidson, BMW, Honda, Kawasaki, Triumph, Tianjin Gangtian, Lifan Motorcycle and Yamaha.The regulations of street motorcycle adopted in 1978, the revision always until 2003, and the new standard of California after having passed through described regulations in 2003.The pollutant of monitoring in the new standard comprises HC, NOx and CO.

The emission control technique that is used for motorcycle includes but not limited to that 2 two-stroke engines are transformed into the Combustion chamber design (higher compression ratio, piston-shaped and nozzle location) of 4 strokes, advanced person's spraying system (injection timing, expulsion pressure, velocity mode, common rail injection and Electronic Control), pulse of air system, change and use catalytic converter.The restriction of motorcycle emission control technology is different from the emission control technique of light or heavy vehicle.Motorcycle is more paid attention to the temperature of outward appearance, layout and after-treatment device, because " hiding " this device is local less, and passenger and exothermic oxidation reaction are much closer.

The category of road engine, equipment and the vehicles that move includes but not limited to agricultural, building, mining industry, gardening, private ship, ship, merchant navy vessel, locomotive, airborne vehicle, snowmobile, cross-country motor and ATVs engine.

Puffer is emitted quite a large amount of air pollutions for its size; They are independently emission sources of the maximum of non-road HC total amount; Puffer equipment include but not limited to fall leaves purging machine, trimmer, brush cutter, chain saw, hay mover, riding mower (engine ridingmowers), riving machine, snowblower and wood chipping equipment.Engine and equipment manufacturers include but not limited to John Deere, Komatsu, Honda, Ryobi, Electrolux (Husqvarna andPoulan also supplies Craftsman), Fuji, Tecumseh, Stihl, American YardProducts and Briggs and Stratton.

EPA begins the standard management puffer that came into force with 1997 in (the I stage) in 1993, and (the II stage) in 2002 continued to reduce emission level with new standard.These standards are divided into portable and non-portable class with equipment, classify based on the engine displacement difference.The discharging of these regulations major control hydrocarbon and nitrogen oxide.

Emission control technique includes but not limited to utilize catalyst (being the LE technology of John Deere and the layered scavenging design of Komatsu), 2 two-stroke engines to be transformed into 4 strokes, advanced person's spraying system (injection timing, expulsion pressure, velocity mode, common rail injection and Electronic Control) or to change Combustion chamber design (higher compression ratio, piston-shaped and nozzle location).

RV market comprises cross-country motor, snowmobile and all-terrain vehicle (ATVs).They are made by manufacturer and the engine supplier of for example Honda, John Deere, Kawasaki, Mitsubishi Motors, Nissan, Toyota, Yanmar, Arctic Cat, Bombardier, Brunswisk, International Powercraft, Polaris, Suzuki and Yamaha.

It is more late than many other markets that EPA begins to manage RV, but the California is managed in advance.EPA manages snowmobile stage by stage from 2006-2009, and 2006-2007 manages cross-country motor and ATVs stage by stage.The pollutant of control comprises HC, CO and NOx.The emission control technique that is used for RV includes but not limited to that 2 two-stroke engines are transformed into 4 strokes, advanced person's spraying system (injection timing, expulsion pressure, velocity mode, common rail injection and Electronic Control), pulse of air or change Combustion chamber design (higher compression ratio, piston-shaped and nozzle location).

In mining industry, department lays down rules and regulations by the mine safety health control.Often think that mining is the most environmentally hazardous, because vibration, bump and the dust of height.Temperature and combustibility also are the problems of comparatively being concerned about in the mining industry.Improved diesel oxidation catalyst on some winning equipments, diesel particulate filter is universal just day by day simultaneously.

In agricultural and construction market, EPA management spark ignition and compression ignition engine.These engines can be used for tractor, forklift, bull-dozer, generator, paving machine, roller press, ditcher, rig, mixer, crane, baling press, compressor etc.Engine and equipment manufacturers include but not limited to: Agco, Komatsu, CNH Global, Caterpillar, Cummins, Daewoo, John Deere ﹠amp; Co, Dueutz, Detroit Diesel and Kubota.

EPA uses Tier 2 (progressively adopting from 2001-2006) raising standard recently in the diesel engine part that 1994 (Tier 1) begins to manage these engines.Due to improving standard once more with Tier 3 levels from 2006-2008.Tier 3 standards may require to use to heavy vehicle (as breakdown trailer) and go up the similar emission control system of employed those emission control systems.The regulations of gasoline, liquid propane gas or compressed natural gas (CNG) engine that uses in agricultural and Application in Building also change recently.Tier 1 standard is in beginning in 2004, with former CARB accepted standard coupling; Tier 2 standards are estimated to begin to carry out in 2007.The voluntary planning of a kind of discharging vehicle lower than standard is arranged, called after " blue sky series ".According to size of engine and fuel type, progressively adopt for meeting at present with very fast with accepted standard, the content of particle, carbon monoxide, nitrogen oxide and non-methane hydrocarbon all must significantly reduce.

That adopts on emission control technique and the heavy vehicle is similar, includes but not limited to advanced spraying system (injection timing, expulsion pressure, velocity mode, common rail injection and Electronic Control), waste gas recirculation, change Combustion chamber design (higher compression ratio, piston-shaped and nozzle location), advanced person's turbocharging, ACERT, diesel particulate filter, NOx absorber, SCR, conventional catalytic converter, catalytic exhaust gas silencer and diesel oxidation catalyst.Waste gas recirculation (EGR) has problems because of it is tending towards generating sulfuric acid at the engine inlet.EGR also needs cooling, bigger radiator must be arranged, thereby make the car front end bigger, causes the restriction of aerodynamics and fuel economy.

In marine vessel applications, engine can still be the still commercialization or divide according to size of engine of diesel fuel, private by using gasoline generally.Marine installation comprises private ship, yacht, ferryboat, towboat and sea-going ship.Manufacturer and engine supplier include but not limited to: Bombardier (Evinrude, Johnson, Ski Doo, Rotax etc.), Caterpillar, Cummins, DetroitDiesel, GM, Isuzu, Yanmar, Alaska Diesel, Daytona Marine, MarinePower, Atlantic Marine, Bender Shipbuilding, Bollinger Shipyards, VT Halter Marine, Eastern Shipbuilding, Gladding-Hearn, JeffBoat, Main Iron Works, Master Boat, Patti Shipyard, Quality shipyards, with Verret Shipyard, MAN B﹠amp; W Diesel, Wartsila, Mitsubishi, Bath IronWorks, Electric Boat, Northrop Grumman (comprising Avondale, Ingalls and Newport News Shipyards).

EPA manages ship, no matter they are amusements with, individual with or commercialization.From amusement with the vehicles to oil tanker, mainly classify based on engine displacement.30 liters of following non-amusements of diesel engine of (30L) discharge capacity comprise fishing boat, towboat, tugboat, dredger and freighter with ship, and the new standard at NOx and PM that came into force between 2004 to 2007 is arranged, and this depends on size of engine.The non-amusement of diesel engine that surpasses 30L comprises cargo-container ship, oil tanker, bulk carrier and pleasure boat with ship, additional HC, PM and the CO standard (Tier 2) that the NOx standard (Tier 1) that came into force in 2004 is arranged and came into force in 2007.Diesel engine amusement ship comprises the amusement ship of yacht, cruiser and other type, the following non-amusement of diesel engine of their standard and the 30L discharge capacity matches criteria of ship, but the time of implementation is later, according to size of engine and from 2006-2009.Gasoline and Diesel Tanker Vessel are just restricted to the HC discharging of outboard motor, individual ship and jetboat recently.Stern drives and original just cleaning, the not restriction as yet of inboard engine.

The emission control technique of using on emission control technique and the heavy vehicle is similar, includes but not limited to spray (injection timing, expulsion pressure, velocity mode, common rail injection and Electronic Control), advanced turbocharging, variable valve timing and change Combustion chamber design (higher compression ratio, piston-shaped and nozzle location) when ship uses during at harbour " green terminal ", 2 strokes to be transformed into 4 two-stroke engines, secondary water cooling, waste gas recirculation, diesel particulate filter, SCR, diesel oxidation catalyst, catalytic converter, advanced fuel.Provide auxiliary power (for example auxiliary power unit APU) also to help the control discharging with less engine.Though salt solution and the pollutant that accompanies thereof and the cooling effect of ship caused the post processing difficulty, APU can work finely with after-treatment device.

Locomotive market mainly relies on diesel fuel (coal combustion and timber restriction are used), comprises the train that is used for shipping and passenger rail, long-distance transport, common car and track switch service.Annual production surpasses 600 trains in the U.S..Manufacturer and engine supplier include but not limited to GM ' sElectromotive Division, GE Transportation Systems, Caterpillar, DetroitDiesel, Cummins, MotovePower, Peoria Locomotive Works, RepublicLocomotives, Trinity, Greenbrier and CSX.

2000 begin train is managed, and mainly imitate the regulations of heavy vehicle.Standard comprises the discharge standard of new production engine and the transformation of the way (about 4-8 carries out once) engine, is used for that track switch is still transported for long-distance and different according to engine.Tier 0 was used for from the engine vehicle year of 1973-2001 (MY), and Tier 1 is used for MY2002-2004, Tier 2 be used for MY2005 and after.The highest every engine Mei Tian $25,000 of being no more than of non-compliant fine.The pollutant of control comprises the opacity (smokeopacity) of particle, NOx, HC, CO and cigarette.

Emission control technique is similar to the emission control technique that adopts on the heavy vehicle, includes but not limited to advanced spraying system (injection timing, expulsion pressure, velocity mode, common rail injection and Electronic Control), waste gas recirculation, change Combustion chamber design (higher compression ratio, piston-shaped and nozzle location), SCR, diesel oxidation catalyst, recoler, share split cooling (split cooling), zeolite molecular sieve and NOx reducing catalyst.Use less auxiliary power unit also to become the emission control strategy, this use to after-treatment device limits still less.

Airborne vehicle market comprises all types of airborne vehicles, comprises the aircraft that Boeing, Airbus, Cessna, Gulfstream and Lockheed Martin etc. make.EPA and European Union all follow the discharge standard of International Civil Aviation Organization (ICAO).EPA adopted the current standard of ICAO about the CO and the Nox of gas-turbine unit in 1997, adopted its HC standard in 1984.In the U.S., the FAA monitoring is also carried out these standards.Many emission controls are finished by the engine technology and the change of fuel.

Stationary source comprises those irremovable pollution sources.EPA has issued the rule that comprises more than 80 class key industry sources, these industrial source comprise power plant, chemical plant, oil plant, Aero-Space manufactory and steel mill, and less source such as drycleaner's, commercial sterilisation device, secondary lead smelting furnace and electrodeposited chromium equipment.The power plant can adopt pollution sources such as fixing Diesel engine, fixing gas turbine and nuclear power.Each of these pollution sources all produces different pollutants; For example nuclear power station produces iodine and hydrogen, and gas turbine produces NOx, CO, SOx, CH ₄And VOCs, refinery produces steam, CO, NOx, VOCs, CO ₂, CH ₄And PM.Every profession and trade needs different control technologys to reduce the airborne contaminants discharging.

The EPA regulations comprise six kinds of index pollutants and 188 kinds of other poisonous air pollutants.Concrete implementary plan comprises the Ozone Transport Commission ' s NOx Budget Program that is intended to reduce the Acid Rain Program of sulphur emissions and is intended to reduce the NOx discharging.RECLAIM is the planning for exchange NOx and the formulation of SOx credit.In addition, rationing transaction planning (cap and trade programms) is carried out in some industries and area, and its emission credit is exchanged by permission company.

The technology that control fixed-contamination source emission is adopted varies, but example comprises that filter, washer, absorber, SCR (SCR), settling vessel, zero loss catalyst, turbine are with catalyst or oxidation catalyst.Some suppliers of stationary source market emission control systems comprise: M+W Zander, Crystall, Jacobs E., Takasogo, IDC, ADP, Marshall, Bechtel, Megte, Angui, Adwest, Eisenmann, CatalyticProducts, LTG, Durr, Siemens and Alston.Catalyst supply merchant comprises: Nikki, BASF, Cormetech, W.R.Grace, Johnson Matthey, UOP and Sud Chemie.

Owing to improve air quality and the importance that meets relevant law and regulations, in the technology that can reduce discharging, dropped into very many times, fund and effort.Three big technical fields comprise: a) engine modifications, b) fuel modification and c) post processing.These approach are not repulsion or independently solution mutually typically.Engine modifications includes but not limited to spraying system, waste gas recirculation, electronic sensor and fuel control, Combustion chamber design, advanced person's turbocharging and the technology of variable valve timing such as the advanced person.Fuel modification includes but not limited to the prescription such as high cetane number, low aromatic hydrocarbons, low-sulphur fuel, fuel carried catalyst (fuel borne catalyst), liquefied petroleum gas (LPG), fuel oxidation, compressed natural gas (CNG) and biodiesel.Post-processing technology includes but not limited to: catalytic converter (2,3 and 4 imitate), particle trapper, SCR, NOx absorber, HC absorber and NOx reducing catalyst or the like.Some systems merge these technology of polylith and other technology; The ACERT of Caterpillar or catalyzed diesel particle trapper are the examples of association system and device.The also restriction use at present of some technology is also arranged, be subjected to technical limitations or be subjected to trade restriction.

Advanced spraying system comprises injection timing, expulsion pressure, velocity mode, air-assisted fuel injection, multi-point injection continuously, common rail injection, adjustment orifice size or movable spray hole and some electronically controlled changes.In common rail system, the petrolift of microcomputerization control flow fuel and timing (for example Mercedes-Benz E320 adopts this system).Secondary air injection can promote the burning of interior HC of manifold and CO.Change spraying system and can reduce multiple discharging, also can improve fuel economy; But this need do extensive work to guarantee efficient on engine.

Waste gas recirculation (EGR) guides some waste gas return engine inlets.By waste gas is mixed with fresh suction air, reduce the amount of oxygen that enters engine, cause discharged nitrous oxides to reduce.EGR does not need time-based maintenance, turns round fine with high whirlpool, the combination of high turbulent combustion chamber.EGR is defectiveness also, for example fuel efficiency and engine life reduce, to the increase in demand of cooling system of vehicle, be limited to no effect the pollutant beyond the NOx, and need control algolithm and sensor.For this reason, EGR often uses with other control technology is parallel.The company that relates to the EGR technology comprises Doubletree Technologies, ETC, STT Emtec, Cummins, Detroit Diesel, Mack and Volvo.

Optimizing the combustion chamber or progressively improving the combustion chamber is another approach that manufacturer and developer control discharging.Reduce the capture (thereby generation of restriction HC) that the crack volume can limit unburned fuel, but and the amount of minimizing lubricating oil also can reduce generation and the limiting catalyst poisoning of HC.Other measure comprises: improve cylinder and piston surface smoothness, improve piston ring design and material and improve exhasut valve stem sealing.Also can make " fast burn " combustion chamber by the following method: improve burn rate, reduce advanced ignition, in air-fuel mixture, add diluent and/or increase indoor turbulent flow.Can cause reducing discharging though optimize the combustion chamber, it is another another technology that need revise engine, and this may be expensive process.

Variable valve timing relates to calibration engine air valve makes its switching reach fuel and engine efficiency maximum.Usually detect engine speed with sensor, regulate the switch of air valve in view of the above.This technology can improve engine torque and power, and can improve eddy current and intake velocity, thereby improves efficiency of combustion.It is many not as some other technology that variable air valve technology reduces discharging, causes fuel efficiency to descend usually.

Again preparing or using different fuel is another kind of emission control technique, because some fuel is bigger than other fuel contamination natively, and some fuel is tending towards making the catalyst poisoning of purifying exhaust air.For example, converting lead-free fuel in the U.S. to from leaded fuel significantly reduces plumbous discharging.The sulfur content that reduces fuel makes SOx discharging minimizing and the efficient of many catalytic converters is improved, because sulphur can make catalyst poisoning.Another kind of fuel natural gas typically produces than diesel fuel particle still less and pollutes and can reduce NOx and combustion noise.On the contrary, natural gas can also make car weight increase (because needing pressure pan) and have the restriction that refuels.

Adopt after-treatment device (equipment that uses after the fuel combustion) very common in the industry that some is influenced by the emission control management.An example of after-treatment device is a catalytic converter.Catalytic converter can vary and can have difference in functionality, but generally is meant the device with catalyst treatment waste gas.In these years, composition of catalyst changes to some extent on base material and its, and the layout and the quantity of converter also change.

The economic benefits and social benefits catalytic converter carries out the oxidation of gas phase pollution, for example HC and CO is oxidized to H ₂O and CO ₂Diesel oxidation catalyst (DOCs) is the another kind of economic benefits and social benefits catalytic converter that uses with Diesel engine.Though these converters are controlled HC and CO effectively and need be maintained hardly, they can increase the NOx discharging and to sulfur sensitive.

Triple effect catalytic converter carries out oxidation and (CO and HC is changed into CO ₂And H ₂O) and the reduction (NOx is changed into N ₂Gas) reaction.Since nineteen seventies, triple effect catalytic converter is reducing vehicular discharge always.Further improving performance with these devices limited by the surface area and the catalyst poisoning of many factors such as temperature range and device base material.For meeting the regulations of increasingly stringent, some automobile needs a plurality of catalytic converters.

The quadruple effect catalytic converter carries out oxidation and reduction reaction, and trap particulate matter is to burn it (can initiatively or passive mode regenerate).

The supplier of catalytic converter and pass parts thereof includes but not limited to Corning, NGK, Denso, Ibiden, Emitec, Johnson Matthey, Engelhard, Catalytic Solutions, Delphi, Umicore, 3M, Schwabische Hutten-Werke GmbH (SHW); Hermann J.Schulte (HJS), Clean Diesel Technology, Cleaire, Clean AirSystems, ArvinMeritor, Tenneco, Eberspacher, Faurecia, Donaldson and Fleetguard.

Micro particle catching or filter are another kind of after-treatment devices commonly used in the diesel fuel applications, because diesel fuel produces than gasoline or some alternative fuel more particles things.In diesel engine particle catcher (DPT), the particulate in the waste gas stream is by collecting their filter.Remove the particle of collecting on the trap and be called " regeneration ", can carry out in many ways.A kind of method makes the temperature of filter rise to the required level of " burning " PM with external heater.Other method discharges a spot of diesel fuel in waste gas stream.During the contacted filter of fuel particles, fuel is burnt under heating up.This higher temperature is also burnt the PM in the filter.Other method is to promote regeneration with the fuel carried catalyst again.In another approach that is called " catalyzed diesel particle trapper ", catalyst directly is applied to filter itself, makes to burn the required temperature reduction of PM.At last, can before filter, utilize oxidation catalyst to promote to burn PM.The system that the cyclic regeneration trap (CRT) of Johnson Matthey comes to this.Diesel engine particle catcher can reach 85% with the PM reduction in some applications.Except PM, the trap that utilizes catalyst also useful catalyst (as previously mentioned) reduces other pollutant (for example HC, CO and PM).On the contrary, these traps may be stopped up by PM, cigarette ash and ash content, and the catalysis variant may be poisoned.These also make the cost of vehicle and weight increase.

Diesel engine particle catcher can use many dissimilar filters, comprise: the overall structure porous fibre (Corning of pottery, NGK), the filter (3M) that twines of fiber, braided fiber (BUCK), weaving fiber (HUG, 3M), sintered metal fiber (SHW, HJS) or filter paper etc.The supplier of these devices and correlation technique thereof includes but not limited to Donaldson, Engelhard, Johnson Matthey, HJS, Eminos, Deutz, CoRrning, ETG, Paas and EngineControl Systems.

SCR (SCR) is another example of after-treatment system.In this technology, before arriving catalyst case, waste gas adds the chemicals such as the urea that can play the reducing agent effect.Hydrolysis of urea generates ammonia.NOx in ammonia and waste gas reaction produces N then ₂Gas, thus the NOx discharging reduced.Ammonia can directly inject or keep solid urea, urea liquid or crystal form.Oxidation catalyst often and SCR is parallel uses to reduce CO and HC.Regrettably, though SCR reduces NOx effectively and catalyst decay is little, fuel economy is good, needs extra jar and the foundation structure that refills this jar on vehicle.Also depend on end user's agreement; Need company and driver to refill described jar to keep emission control.The supplier of SCR or its parts includes but not limited to Engelhard, Johnson Matthey, Miratech Corporation, McDermott, ICT, Sud Chemie, SK Catalysts and PE Systems.Though only use in the U.S. limitedly, expection SCR will be widely used for Europe to reduce discharging, particularly in heavy truck market.

NOx adsorbent be under the poverty of fuel state, store NOx and under fuel-rich state (typically per a few minutes) discharge and the material of catalytic reduction of NOx.This technology all can be used in gasoline and diesel fuel applications, although gasoline provides better rich fuel, hot environment.NOx adsorbent reduces the content of HC, NOx and CO, but PM is not almost affacted not effect.They can work under wide temperature range.On the contrary, the NOx adsorption capacity reduces according to temperature, needs engine control and sensor, and the sulfur content of fuel suppresses or makes the loss of function of Nox adsorption capacity.In diesel fuel applications, extra constraint is arranged, comprise the formation of the amount, HC utilization rate, temperature range and cigarette or the particulate that have oxygen in the waste gas.

The NOx reducing catalyst also can be used for the control discharging in the following manner: 1) initiatively injected reducing agent and/or 2 to system before catalyst) use the wash coat of zeolite with absorption HC, thus produce the zoneofoxidation that is of value to reducing NOx.Though this technology can reduce NOx and PM, more expensive than many other technology, and may cause fuel economy difference or sulphate particle.

The HC adsorbent is designed for when catalyst treatment low temperature and captures VOCs and just discharge VOCs when catalyst is heated then.This can realize by the following method: 1) adsorbent is applied directly on the substrate for catalytic converters, consider small variation but control less, 2) adsorbent is placed in the independent but continuous before blast pipe of catalytic converter, and free gas shift passage is arranged when converter is heated, and/or 3) adsorbent is placed on after the catalyst.The two kinds of options in back need the cleaning option of adsorbent.Though this technology reduces cold start emission, be difficult to control and increase cost.

Be difficult to control owing to proved discharging, so in the system of being everlasting, unite emission control technique.The example of association system comprises DeNOx and DPT (as HJS ' SCRT system), place catalytic converter in the silencer, with integrated SCR or the catalyzed diesel particulate filter of silencer.

ACERT is another example that merges the system of multiple emission control technique.ACERT from Caterpillar has four target areas: air inlet processing, burning, electronics and exhaust after-treatment.Crucial parts comprise the single and serial turbocharging that is used to cool off air inlet; Be used to improve the variable air valve execution of fuel combustion; The electronics multichannel that is used for integrated computer control drives; With the catalyzed conversion that is used to reduce the tailpipe particulate emission.These subsystem cooperations make company can increase fuel-economizing.The significant drawbacks of this technology is the catalyst that needs large volume.

Many other emission control technique are arranged, and some of them are still infeasible technically.

Catalytic converter

The concern of the pollution that is caused by automobile for part causes air cleaning decree in 1970, and this decree requires automobile exhaust gas to reduce 90%.Some reduce disputable to this pressure, but generally believe that air and better health that this pressure reduces for cleaning are a kind of progress.

The new regulations that propose of the initial opposing of auto industry.The part opposing may come from the industrial development that improves fuel.From mid-term nineteen twenties to the eighties mid-term, motor petrol fuel comprises additive lead tetraethide (TEL).TEL is by preventing that advanced ignition improves fuel performance in the cylinder.Advanced ignition takes place during the fuel/air mixture premature firing in the engine chamber.This causes damage to engine and descends because of pinking causes efficient and power.

For reaching the reduction discharge standard of statutory regulation, the engineer has invented catalytic converter.Catalytic converter approximately joined vehicle exhaust system since 1976.Catalytic converter is reduced to discharging to a certain degree effectively.But the regular gasoline prescription that contains TEL disturbs the function of catalytic converter.Because the TEL in the fuel poisons the metallic catalyst of catalytic converter, so finally removed TEL from fuel.

Though many people may know most vehicle catalytic converter is arranged, generally do not understand this technology.The purposes of catalytic converter is compound such as the nitrogen (N that pollutant waste gas is transformed or becomes the harmfulness reduction ₂, account for atmosphere about 78%), water (H ₂O) and carbon dioxide (CO ₂, photosynthetic product in the plant).

Use catalytic converter to impel undesirable pollutant to change into harmless relatively molecule such as N ₂, H ₂O and CO ₂Catalytic converter mainly provides pollutant to change into the surface of harmless relatively product thereon.Catalyst by reduce required activation energy make reaction quickly (or more low temperature under) carry out.But catalyst does not run out of in reaction and can reuse (unless catalyst poisoning).

Typical pollutant in the waste gas comprises nitrogen oxide (NOx), unburned hydrocarbon, carbon monoxide and particle.Nitrogen oxide can be reduced generation nitrogen.NO or NO ₂During the molecule contact catalyst, catalyst impels this molecule denitrogenation, with O ₂The formal solution deoxygenation.The nitrogen-atoms reaction that is attached to then on the catalyst generates N ₂Gas: With 。

Carbon monoxide, unburned hydrocarbon and particle further oxidation generate the uncontamination thing.For example, processing carbon monoxide as follows: 。

The overall result of catalytic converter is to make fuel completing combustion generate the uncontamination thing.

Conventional catalytic converter is having many restrictions aspect the efficient of destroy contaminants.For example, if the too close engine in position may break soon because of overheated or variations in temperature.In fact strict, the filter of conventional catalytic converter can not be close to enmgine exhaust or be positioned at it, and this is to be cooled off by the radiation of the thermal conductivity Gao Suozhi of blast pipe material to cause temperature decline to utilize the optimum position of on-the-spot high temperature before.Near the exhaust manifold and the inner engine luggine that exists and the rapid variation of temperature may cause the conventional filtration modulator material tired and significantly shorten life-span of filter.In addition, some catalyst that is used for the conventional filtration device high temperature promptly more than 500 ℃ efficient lower or do not work not even again.Therefore, conventional catalytic converter filter is usually located in the exhaust passage position away from engine.

The structure of catalytic converter and particulate filter

Diagram illustrates the parts and the material of catalytic converter among Fig. 4 a and the 4b.With wrapped pad (making by ceramic fibre usually) catalyst substrate is remained in the converter housing (being also referred to as jar).Converter links to each other with vehicle exhaust system by terminal cone, and terminal cone can be welded on the housing or with housing and make parts, depends on the converter package technique.Another parts end envelope and/or support steel ring are optional shown in the figure; Usually there are not these parts in the modern bus converter, but may need in large-scale converter or diesel particulate filter at more overcritical application such as integrated converter, heavy-duty engine.Catalytic converter those catalytic converters during especially gasoline is used also can be equipped with steel hot baffle (not shown) not to be exposed to excessive temperature to protect adjacent vehicle part.

Catalytic converter is made up of at least five critical pieces usually: 1) base material; 2) catalyst coatings; 3) wash coat; 4) jar bed course (matting) and 5).Conventional catalytic converter shown in the figure X.During some is used, describe in detail as the back, catalyst coatings is optional.

Base material

Base material is the surface of solids that pollutant can be changed into the uncontamination thing thereon.Physically, base material provides the interface to react to each other for many molecular species of any physical state such as solid, liquid or gas.Base material generally has big surface area so that the large tracts of land that can pollutant be changed into the uncontamination thing thereon to be provided.

In the past few decades, many different materials and design have been tested as the chemical reaction base material.For example, the main physical structure comprises cellular overall structure and beading (bead) structure.(referring to Fig. 1).Alveolate texture comprises many passages, and the length direction along base material is parallel to each other usually.Base material has the passage that passes base material length.The channel width difference depends on host material and application thereof usually.These passages allow waste gas to flow by catalytic converter from engine, and discharge by blast pipe.By in the base material channel flow, contaminant molecule changes into uncontamination thing molecule by chemical reaction and physical change at waste gas.

In beading structure, base material is made (be similar to and place a string jelly beans in pipe) by a pile beads.Waste gas can be walked around bead mobile (by passage and crack).Pollutant changes into the uncontamination thing when waste gas collides these beads.Beading structure is to maximize one of early stage trial of carrying out for the substrate surface that makes the emission molecule contact is long-pending.

Many different materials are used as base material.These comprise pottery, fiber reinforced ceramic matrix composites (FRCMC), foams, ceramic powder, nano composite material, metal and fiber mat type base material.The most frequently used is the pottery that is called cordierite, is produced by Corning.Cordierite is the pottery that is formed by fire-resistant powder.FRCMC is a kind of open-celled foams, and wherein catalyst arrangement is on hole wall, and foams are arranged in the duct that makes waste gas must pass foams in the catalyst converter and leave.Foams are the solids that contain many holes, and these holes are by bubble and fire the space and form.The ceramic powder base material is that with the difference of cordierite and relevant pottery ceramic powder is formed by sintering ceramic powder.Nano composite material is to adopt the material of nanometer powder and/or nanofiber.Also available metal is made base material.Generally the thin slice with corrugated metal forming such as steel is rolled into alveolate texture.Fiber mat type base material is the woven material of small-scale.The NEXTEL fiber that some fiber mat type base material adopts 3M to produce.In addition, also try out " two dimension " non woven fibre composite, and utilized the rivel and/or the ripple that fold out to form honeycomb.For example, referring to US4,894,070,5,196,120 and 6,444,006B1.

Catalyst coatings

The 3rd parts of catalytic converter are catalyst coatings at present.Hint that as its title catalyst coatings is that in fact the catalysis pollutant changes into the component of uncontamination thing.

Catalyst is normally defined and influences chemical reaction rate but be not the material of one of primitive reaction thing or end product, and promptly it does not consume in reaction or changes.In several known mechanisms of catalytic reaction, catalyst and reactant form intermediate compound but restore in course of reaction.Many other catalytic process are fully explained as yet or are all understood.Decision is not fully explained for the principle of the selection of specific purposes and preparation catalyst yet or is all understood.Comprise the test numerous materials by meticulous exploration scheme, a lot of progress have been obtained in this field.Catalyst is widely used in chemistry and petrochemical process, and promotion is too slow or need high temperature to obtain the reaction of good efficiencies.Catalyst also is used for the harmful constituent of engine exhaust such as hydrocarbon and carbon monoxide are changed into innocuous substance such as carbon dioxide and steam.

Catalyst is the material that can quicken some chemical reaction between the waste gas component.In emission control catalysis, come catalytic gas phase reaction with solid catalyst.By contacting providing sufficient between gas phase and the solid catalyst, make catalytic action and the maximization of observation reaction rate.In catalytic reactor,, thereby realize described abundant contact often by making the catalyst high degree of dispersion on the carrier (carrier) of high-specific surface area, provide high catalytic surface long-pending.

Apply catalytic coatings to base material after forming base material.Coating forms layer on substrate surface, this layer contains catalyst.According to for example chemical reaction, required application, temperature conditions, economic factor etc., need dissimilar catalyst.Many metallic catalysts known in the art.For example, the most frequently used is platinum, palladium and rhodium.Done number of research projects for the exploitation raw catelyst.

Chemical reaction comprises that the speed of catalytic reaction generally improves with the temperature rising.It is the feature of all emission control catalysts that transformation efficiency has very strong dependence to temperature.With solid line (A) the catalyzed conversion speed of pollutant and the typical relation between the temperature are shown among Fig. 4.Conversion ratio, slowly increases earlier near zero at low temperature, more promptly increases then, is issued to maintenance level at high gas temperature.When combustion reaction was discussed, the Essential Terms firing temperature characterized this character.Catalytic ignition is to cause the required minimum temperature of catalytic reaction.Because reaction rate increases gradually, above-mentioned definition is not very accurate.According to definition more accurately, firing temperature is the temperature that conversion ratio reached 50% o'clock.This temperature is typically expressed as T ₅₀Relatively during different catalysts active, higher for the minimum expression catalyst activity of firing temperature of given reaction.

In some catalyst system, the rising temperature can only make transformation efficiency be increased to and be no more than certain a bit, shown in dotted line among Fig. 4 (B).Further the rising temperature although reaction rate is increased, causes the catalyst transformation efficiency to descend.Usually explain decrease in efficiency with other competitive reaction of consumption reaction substrate concentration or with the thermodynamical reaction equilibrium-limited.

Temperature range corresponding to high transformation efficiency is commonly referred to the catalyst temperature optimum range.This type of inversion cuver is the feature of selectivity catalytic process.Good example comprises with hydrocarbon or ammonia selective reduction NO.

Another significant variable that influences transformation efficiency is a reactor size.Gas flow rate by catalytic reactor generally is expressed as air speed (SV) with respect to reactor size.Air speed is defined as the gas volume of the time per unit monomer volume reactor of measuring down in the status of criterion (STP), as (3) SV=V/V _rShown in, wherein V is the gas volume flow velocity under STP, m ³/ h; V _rBe reactor volume, m ³With the dimension of SV be the inverse of time, often with l/h or h ^-1Expression.

In various catalysis emission controls were used, air speed was 10, and 000l/h to 300 is in the scope of 000l/h.The air speed of overall structure reactor is based on its external dimensions for example diameter and the length computation of cylindrical ceramic catalyst substrate.Because this method is not considered geometrical surface, hole density, wall thickness or the catalyst load of base material, so always be not fit to catalyst relatively.But, it is commonly used and universally recognized industrial standard.

Nineteen nineties cross-country engine with typical platinum load in the filter at 35g/ft ³To 50g/ft ³Between.These filters are installed on the big relatively engine of pollution, need regenerate near 400 ℃ minimum temperature.Afterwards, when the city bus that catalytic filter is used to clean manyly and the engine of other highway communication instrument, found that they can regenerate under much lower temperature.But need higher platinum load to keep low-temp recovery.The typical platinum load of cleaning engine filter device therefor in cryogenic applications is 50-75g/ft ³

Wash coat

In most cases, catalyst coatings comprises that wash coat is as the 4th part.Wash coat is applied to substrate surface, thereby increases the surface area of base material.The surface that wash coat also provides catalyst to adhere to.Metallic catalyst can be immersed on the layer of this porous high surface of inorganic carrier, (being wash coat-available term " catalyst carrier " expression ceramic/metal base material and carrier/wash coat material).

Many materials can be used as wash coat.The material that is widely used in catalyst carrier comprises activated alumina and silica (silica).

Wash coat is the porous high surface layer that is combined on the carrier surface.Its accurate function is very complicated really, does not understand as yet or gets across.The main effect of wash coat provides and disperses the needed very high surface area of catalytic metal.In addition, but thereby the wash coat physical separation prevents to take place between the component of complicated catalyst system and catalyzing the reaction do not expected.

The material of wash coat comprises inorganic base metal oxide such as Al ₂O ₃(aluminium oxide or alumina), SiO ₂, TiO ₂, CeO ₂, ZrO ₂, V ₂O ₅, La ₂O ₃And zeolite.In them some are as catalyst carrier.Adding in the wash coat of other as co-catalyst or stabilizing agent.Also have some to show the catalytic activity that itself has.Good wash coat material characteristics is specific area and heat endurance height.Specific area combines mensuration by the nitrogen absorption measurement technology with mathematical simulation, is called BET (Brunauer, Emmet and Teller) method.Heat endurance is exposed to high temperature evaluation by making given materials samples usually in the presence of oxygen and steam under the atmosphere of control.The BET surface area losses that remeasures at interval at different time in the process of the test shows the hot degradation of test material.

Wash coat can be applied to catalyst carrier by water base slurry.Dry and the calcining at high temperature with wet patch basal plane coated portion then.The quality of catalyst wash coat can have significant impact to the performance and the durability of finished catalyst.Because noble metal is applied to the washcoat coated portion by dipping subsequently, promptly use catalyst solution " to soak into " hole of wash coat, so the load of wash coat will determine the load of noble metal catalyst in the finished product.Thereby the washcoat coated technique produces favorable repeatability and wash coat is very important very uniformly.All catalyst manufacturers all with the details of washcoat coated technique and parameter thereof as Commercial Secret Protection.

Jar

Base material is packaged into jar for example forms catalytic converter in the steel sheel.Jar has multiple effect.It holds catalyst substrates and protects base material to avoid external environment influence.In addition, jar forces waste gas to pass catalyst substrates and/or flows on catalyst substrates.

Catalyst substrates also can be packaged in the silencer, then is called " catalyst silencer " or " catalytic muffler ".In the case, a cylinder of steel had both held catalyst, held noise-cut assembly such as baffle plate and void channels again.The catalyst silencer can provide with the combination of catalytic converter and silencer and compare the design of more saving the space.

Catalyst substrates places in the jar usually, has the configuration of making by one of several method, comprising: clam shell, tie (tourniquet), footwear box, filling and forging, as shown in Figure 28.

Bed course

Except jar, also with course catalyst substrates is packaged in the jar usually.Wrapped pad is made by ceramic fibre usually, can be used for protecting base material and distributes equably from the pressure of housing.Pad generally includes vermiculite, and it at high temperature expands, thereby compensates the thermal expansion of housing and enough chucking powers are provided under all operations condition.

For example, integral ceramic structure is wrapped in the extra package material, and the extra package material is contained in the overall structure pottery in the box hat safely, equably distribution pressure and prevent to break.Pack the catalytic converter of gasoline and diesel fuel applications with ceramic fibre mat mostly.These wrapped pad can followingly be classified: (but heat expansion) pad expands; Conventional (high vermiculite); Low vermiculite; Unexpansive pad or mixed mat.

Adiabatic

In many application, must make the catalytic converter thermal insulation to avoid damaging surrounding vehicles assembly (for example plastic components, fluid hose) or to prevent that in the converter that more adjacent engine is installed cabin temperature from raising.One of converter thermal management method is to adopt to place to transform body steel hot baffle on every side.Other method is to increase thickness or (2) that pad is installed by (1) to provide the extra play that special-purpose lower thermal conductivity insulate that heat insulation layer is provided in housing.Though under the floor, use hot baffle traditionally always, pad is thick provides best solution (Said Zidat and Michael Parmentier for the converter that is installed in the cabin but proposed to increase, " Heat InsulationMethods for Manifold Mounted Converters; " Delphi AutomotiveSystems, Technical Centre Luxembourg, SAE Technical Paper Series2000-01-0215).Use than hassock but not one of advantage of hot baffle to be the mean temperature of pad lower, this makes the danger that destroys the vermiculite pad reduce to minimum in integrated petrol engine is used.

Grain catcher

Another device of removing pollutant from waste gas is a grain catcher.The plain particles trap that uses on the Diesel engine is diesel engine particles trap (DPT).The main application of grain catcher is the particle of various sizes during filtration and traps fluid stream flow as waste gas.The validity of particulate filter is generally filtered for example ability tolerance of PM-2.5 and PM-10 of different size PM with it.

The diesel engine trap is effective relatively remove carbon black from diesel engine exhaust aspect.The most widely used diesel engine trap is a wall-flow filter, filters diesel exhaust by catch cigarette ash on the porous wall of filter body.Wall-flow filter is designed under the situation of not obvious obstruction waste gas stream and almost completely leaches cigarette ash.

Because soot layer accumulates in the surface of filter inlet passage, the low-permeability of soot layer produces the pressure drop pass filter and filter and raises gradually with respect to the back pressure of engine, causes engine running more difficult, thereby influences power operation efficient.At last, pressure drop becomes and can not accept and must make filter regeneration.In the conventional system, renovation process relates to the filter heating to cause the carbon black burning.Under some situation, under the controlled condition of maneuvering engine, realize regeneration, cause smoulder thus and continue many minutes that the temperature in the filter is from about 400-600 ℃ of maximum temperature that rises to about 800-1000 ℃ during this period.

During some is used, because along with waste gas stream outwards carries the combustion heat and the cumulative effect of the soot combustion ripple that advances in face of export-oriented from filter inlet along filter, the maximum temperature in the regenerative process is tending towards appearing at the neighbor filter port of export.Under some situation, when so-called " not having control regeneration " occurring when rich oxygen content and low flow velocity (as race of engine state) take place or take place following closely in the waste gas with taking fire simultaneously.Do not having the control regeneration period, soot combustion may produce temperature peak in filter, and this may thermal shock and breaks or even melt filter.The most normal observed thermograde be wherein the filter center temperature than the high radial symmetry gradient of base material remainder temperature and filter outlet end axial-temperature gradient than base material remainder heat.

Except that capturing carbon black, filter is metal oxide " ash " grain that carries of capture in flue gas also.Usually, these dust stratifications come from the not combustion lubricating oil of following waste gas under some condition.These particulates can not burn, thereby do not remove in regenerative process.If but temperature is enough not high in having the control regenerative process, ash may final sintering arrives filter or even causes partial melting with the filter reaction.

Obtain the improved filter of refractory voltinism and heat shock resistance infringement property, thereby many controls that filter can not only be held out against in its useful life period are regenerated, and can hold out against the number of times much less but more violent nothing control regeneration, this will be the progress in this field.

The cyclic regeneration trap

A kind of conventional method that is used for catalyzed conversion is diesel engine particles trap (" DPT ").DPT is a filter of collecting particle in the waste gas.Must before filter is blocked, burn the particle of collection then.Burn particle and be called " regeneration ".There are several conventional methods to be used to make DPTs regeneration.The first, it is temperature required to reduce the particle oxidation at filter surfaces coating noble metal catalyst or base metal catalysts.The second, filter can produce NO ₂The chamber that comprises oxidation catalyst after, this helps to burn particle.The 3rd, system can use the fuel carried catalyst.At last, can utilize external heat source, wherein under the situation of catalyst-free cigarette ash 550 ℃ of burnings, perhaps in the presence of noble metal catalyst in about 260 ℃ of burnings.Regeneration stays lime-ash along with carbon burning, needing constantly, maintenance comes cleaning and filtering.

Another conventional method is utilized diesel oxidation catalyst (" DOCs ").DOCs is the catalytic converter of oxidation CO and hydrocarbon.The activity of hydrocarbon extends to the solvable organic fraction (" SOF ") of polynuclear aromatic hydrocarbons (" PAHs ") and particle.Developed selective oxidation SOF and with the minimized catalyst formulation of the oxidation of sulfur dioxide or nitrogen oxide.But DOCs can produce sulfuric acid and increase NO ₂Discharging.

The effect of catalyst is to reduce soot combustion temperatures in the catalyzed diesel particulate filter (CDPF), thereby promote the regeneration of filter, this is to finish by oxidated diesel oil machine particle (DPM) under the delivery temperature (usually in 300-400 ℃ of scope) of experience during running well in engine/vehicle.Under the situation that does not have catalyst, DPM can seldom have so high temperature above oxidized with very high speed under 500 ℃ the temperature in the Diesel engine in the actual mechanical process.Base materials employed cordierite and carborundum wall-flow type overall structure, silk screen, porous ceramics and the ceramic fibre medium etc. of comprising during these catalyst of having reported are used.The most frequently used CDPF is a catalytic ceramics wall-flow type overall structure.

The catalytic ceramics trap is the exploitation early 1980s.Their application the earliest comprise diesel-powered car and underground mining machine afterwards.The California was introduced catalytic filter in 1985 with commercial system and is used for commercially available Mercedes automobile.There are the Mercedes type 300SD and the 300D of turbocharged engine to be equipped with 5.66 " diameter x6 " filter of between engine and turbocharger, installing.

Afterwards because problems such as durability deficiency, pressure drop increase and plugged filter have abandoned using the diesel engine trap on automobile.At present, even these problems are not all to solve, but the catalytic ceramics trap is still one of most important diesel filter technology.The use of CDPFs in many heavy-duty applications such as urban transit bus and city diesel truck is increasing.For many years, underground mining (North America and Australia) and some stationary engine have also used limited amount catalytic filter in using.

Commercially available to being used for the catalytic ceramics filter that many highways, cross-country and stationary engine are used, as OEM and accessory (improvement) product.Some less emission control manufacturers that supplier comprises Engelhard, OMG dmc2 and mainly specializes in cross-country market.

The primary clustering of conventional filtration device is pottery (typically being cordierite or SiC) wall-flow type overall structure.Integrally-built porous wall scribbles active catalyst.The smog infiltration of discharging along with diesel engine is by these walls, soot particulates be deposited in the cinclides network structure and inlet channel surperficial on.The dioxygen oxidation DPM that exists in the catalyst promotion waste gas.

Pressure drop

A large amount of back pressures are given birth in waste gas miscarriage by conventional catalytic converter.The back pressure accumulation is the important symbol of catalytic converter success in the catalytic converter.If catalytic converter partly or entirely stops up, then will in gas extraction system, produce restriction.Back pressure accumulation subsequently will cause engine performance (for example power and moment of torsion) and fuel economy sharply to descend, if stop up seriously, even may cause stopping working behind the engine start.The tradition trial expense that reduces pollutant emission is very high, because material and improvement or manufacturing have the original engine cost of suitable filter all very high.

With high relatively pressure drop is the filtration efficiency that cost obtains wall-flow filter, and pressure drop increases and increases along with filter soot load.Initial filter cleans.Begin to be deposited on along with particle in the hole of overall structure wall (in-depth filtration), pressure drop begins to increase in time with nonlinear way.This stage is called the original upload stage, and the attribute in hole such as permeability and filter hole rate change because of smoke deposition in the network structure in hole constantly increases constantly during this period.After the filtration capacity in hole reached capacity, cigarette ash began to be deposited as one deck (cake filtration stage) in integrally-built inlet channel.Observe pressure drop (with cigarette ash load) linear increasing in time during this period.The thickness that character is soot layer that changes.The short transition time stage in the middle of some author also picks out, begin when channel surface deposits, to be completed into (Tan from particle until soot layer, J.C., et al., 1996, " A Study on the Regeneration Process in Diesel ParticulateTraps Using a Copper Fuel Additive ", SAE 960136; Versaevel, P., et al., 2000, " Some Empirical Observations on Diesel Particulate FilterModeling and Comparison Between Simulations and Experiments ", SAE2000-01-0477).

Finished the drop simulation in the cleaning and filtering base material.The simple relatively models show of having developed goes out the uniformity (Masoudi fabulous with result of the test, M., et al., 2000, " Predicting Pressure Drop of Wall-Flow Diesel Particulate Filters-Theory and Experiment ", SAE 2000-01-0184; Masoudi, M., et al., 2001, " Validation of a Model and Development of a Simulator for Predictingthe Pressure Drop of Diesel Particulate Filters, " SAE2001-01-0911).Yet the pressure drop of practical application middle filtrator is produced by smoke deposition mostly.In the practical application, the pressure drop of cleaning wall-flow filter can be in the scope of 1kPa to 2kPa, and that the loading filter pressure drop of 10kPa can be thought to be low to moderate in some cases is medium.

The overall presure drop that loads the particulate filtration device can be divided into following four parts: because of filter inlet and outlet sudden contraction and the pressure drop of expanding and producing; Because of the fricative pressure drop of conduit wall; The pressure drop that produces because of the permeability of stratum granulosum; With the pressure drop that produces because of the permeability of wall.

Because of filter inlet and outlet sudden contraction and the pressure drop that expand to produce similar with the same section of cleaning and filtering, except now effective channel size (hydraulic diameter) because of soot layer becomes littler, cause contraction of gas more.

Because of the fricative pressure drop of conduit wall also increases than under the cleaning and filtering situation, because the hydraulic diameter of passage reduces.During the cigarette ash bed thickness, Δ P passage can be the important factor in order of overall presure drop.

The pressure drop (Δ P particle) that produces because of the permeability of stratum granulosum can be the important factor in order of overall presure drop.

Now the pressure drop (Δ P wall) that produces because of the permeability of wall is also than the height in the cleaning and filtering, because cinclides is partly filled by cigarette ash.Represent to be attributable to the increase of the Δ P wall of initial cigarette ash load phase in the hole among Fig. 3 with Δ PI.

Overall presure drop can be expressed as follows:

Δ P=Δ P inlet/outlet+Δ P passage+Δ P particle+Δ P wall

The mathematical simulation of pressure drop becomes the work of complexity and difficulty in the diesel filter of loading cigarette ash.The critical nature of cigarette ash such as permeability and packed density depend on application, engine operating status and other parameter.Make great efforts to simulate the pressure drop in the wall-flow filter, and developing superior day by day model.The theoretical model that may need regenerative process itself to the prediction of the cigarette ash load of reality.

The type of catalytic converter and particulate filter

Catalytic converter can be classified according to many factors, these factors comprise: the type of a) using the engine of converter on it, b) catalytic converter is with respect to the position of engine, c) quantity of catalyst system therefor and type in the converter, and d) base materials employed type and structure.In addition, each of these catalytic converters is all united use with other emission control system such as CRT, EGR, SCR, ACERT and other device and method usually.

Engine

At least two class engines are to use catalytic converter on gasoline and the Diesel engine.Special gasoline and Diesel engine that many types are arranged in this two big class.For example, make gasoline and Diesel engine with different displacements and power.Some engine is furnished with turbocharger and/or intercooler.Most of automobiles and truck engine are water-cooleds, and many motorcycle engines are air-cooled.Some application need can obtain high power, and other application requirements fuel economy maximum.All these variablees and other variable all may influence the degree that produces pollutant in the fuel combustion process.In addition, the purposes that depends on engine is road, cross-country or fixing for example, and discharge standard is had different management expectancys.

The position

Catalytic converter can be installed in any position along engine exhaust stream in theory.But the physical characteristic of conventional catalytic converter limits its position.Modal in the vehicle is that catalytic converter is installed in some distance of engine block, near silencer and the position below vehicle body.Catalytic converter keeps clear of engine usually and installs, because catalytic converter may lose efficacy because of several reasons.These reasons comprise near the spatial constraints extreme temperature, thermal shock, mechanical oscillation, mechanical stress and the engine.And, the position that the physics equipment of stationary engine may limit catalytic converter or particulate filter.

For example, at its 2004 FOCU.S. ^TMIn, Ford Motor Company has disposed the manifold catalytic converter, as Honda Motor Corporation in one of its product.These systems are in fact adjacent with manifold, but not the part of manifold.Higher temperature that cylinder outburst and moving-member are produced and extreme vibrational energy make present catalytic converter (if placing in the manifold) be subjected to great thermal shock and mechanical shock.In addition, Northup Grumman Corporation is at US 5,692, proposes the design of manifold catalytic converter in 373.It is believed that even also there is the situation of this environment of tolerance challenge in present cordierite substrates.

In other application examples such as motorcycle (as Harley-Davidson), exist catalytic converter to cause serious injury to the user in some position.Because the operating temperature height of catalytic converter, the preferred use is difficult for catalytic converter that the user is damaged, the converter of for example less catalytic converter, the heat like this of not becoming etc.

Under some situation, gas extraction system (for example in the automobile) may comprise more than a catalytic converter or particulate filter along its exhaust stream.(referring to Fig. 4).For example, gas extraction system can have another catalytic converter between engine and main catalytic converter.This configuration is called pre-catalytic converter (pre-cat).Pre-catalytic converter can have closeer configuration.Another kind of assembling is a back catalytic converter (back-cat), has the secondary catalytic converter that is positioned at main catalytic converter back (or afterwards).Back catalytic converter also is used to improve catalytic converter sometimes.

Economic benefits and social benefits, triple effect and quadruple effect

Catalytic converter generally can be divided into economic benefits and social benefits, triple effect or quadruple effect converter.At least commercially available converter to following type: oxidation conversion device, triple effect converter (no air), triple effect add oxidation converter and quadruple effect converter.

Oxidation (economic benefits and social benefits) converter representative generation converter early is designed for hydrocarbon (HC) and carbon monoxide (CO) oxidation.Though these devices are represented the catalytic converter technology of citation form, the selection that reduction that they remain feasible in some zone is polluted.The oxidation conversion device contains platinum or palladium usually.But also can use other base metal.

The phase early 1980s, most Railway Car Plants bring into use and are designed for except that will also reducing the converter of NOx HC and the CO oxidation.These triple effect converters use with computer-controlled engine system and lambda sensor, are used for controlling more accurately air-fuel ratio.These converters are called the triple effect converter, because they handle three kinds of compound: HC, CO and NOx.

Most Hyundai Motors are equipped with " triple effect " catalytic converter, and one or more base material series connection are arranged usually, adopt the clay extruding technology of Corning." triple effect " means the emission that described converter helps three kinds of controls of reduction: carbon monoxide, VOC (VOCs, for example unburned hydrocarbon) and NOx molecule.This converter uses two kinds of dissimilar catalyst, i.e. reducing catalyst and oxidation catalyst.

In the triple effect catalytic converter, reducing catalyst is present in the first order of catalytic converter usually, is used to make the oxidation of the nitrogen that takes place in the combustion chamber to drive in the wrong direction.Usually utilize platinum and rhodium to help to reduce the NOx discharging.Oxidation catalyst can be made up of the metal of for example platinum and/or palladium, is usually located at the second area of catalytic converter.

The triple effect converter that has reduction and oxidation catalyst in a shell simultaneously is sometimes referred to as triple effect and adds the oxidation converter.These converters adopt air to spray between two kinds of base materials.This air sprays and helps the oxidation chemistry reaction.

The quadruple effect converter is handled carbon monoxide, nitrogen oxide, unburned hydrocarbon and particle.These comprise for example QuadCAT quadruple effect catalytic converter of Ceryx manufacturing.According to its manufacturer, described catalytic converter reduces to four kinds of main air pollution source-NOx, hydrocarbon, carbon monoxide and particles to make Diesel engine meet the level of 2002/2004 discharge standard.Other comprises US4, those that describe in 329,162 and 5,253,476.

Catalytic converter is finished the required activation energy of expected response by reduction and is promoted reaction as other catalyst.For example, need 550 ℃ temperature if former particle and oxygen reaction are burnouted, the existence that is reflected at catalyst that then this is identical may only need 260 ℃ temperature down.But this makes catalysis system physics be positioned over the bigger engine downstream in space than the low energy threshold, even temperature is lower.Otherwise this catalysis system then need place the higher upstream of temperature.But this is unpractical under present technology because more close engine when placing base material more likely damage.

Diesel engine produces NOx and particle content height CO and the lower discharging of hydrocarbon because of temperature and pressure is high.It is complete when compression and combustion is not so good as with the petrol engine ignitionization.But owing to the mixture with high air content is rarer, diesel oil can provide than the better mileage oil consumption of petrol engine.Three-way catalyst effect in diesel exhaust is bad, because air excess.The NOx reducing catalyst need keep the stoichiometric proportion of fuel and air usually well, and this is not easy to reach in the engine of burning diesel oil.

Catalytic converter technology can be used for various application, comprises internal combustion engine and fixed combustion engine.Internal combustion engine is the most frequently used engine that is used for the vehicles.A device as vehicle exhaust system is installed catalytic converter, makes whole waste gas stream by base material, contacts with catalyst, discharges from tailpipe then.But catalytic converter also can become and relates to for example part of the suitable complication system of injection reaction thing or most advanced and sophisticated engine control algorithm before catalyst of various active strategies.Example is included as the many diesel catalyst systems that reduce NOx and developing.The simplicity of having enumerated in the advantage of catalyst and the attribute of passivity may no longer be applicable to those systems.

The tradition trial that reduces pollutant emission may be very expensive, and partly cause is will improve or make original engine with appropriate filters in the cost of raw material and some application.

Catalytic converter and particulate filter development of technology

The invention that causes the catalytic converter progress be Corning exploitation extrude the cordierite honeycomb overall structure.(referring to US 4,033,779).Since nineteen seventies, removed from waste gas stream with the method and surpassed 1,000,000,000 pounds pollutant, described method utilization be securely fixed in the lip-deep wash coat of uneven base material (being generally cordierite) from expensive and catalyst (platinum, palladium, rhodium etc.) base metal family, be able to take the extreme environment of engine exhaust system.These years this core technology is carried out changes and improvements gradually later on, comprise the layout and composition and the manufacture method that change catalytic converter.But do not overcome as yet not enough substantially arranged still so far.At present, technology status reaches physics and economic limit, only obtains small improvement at considerable cost.

The restriction of base material at present

Though present catalytic converter and particulate filter technology are applicable to the reduction exhaust emission to a certain extent, there are some shortcomings really in present technology.Also there is the unappeasable characteristic of present catalytic converter.Some deficiency is that the base material of used type is intrinsic.Therefore, be used for catalytic converter or particulate filter improvement base material should be to be used as the basic physics of material of catalyst substrate and the obvious progress of chemical attribute at catalytic converter.In addition, the base material that has improved should improve the quality significantly, can make that manufacturer and user are easier meets 2007,2010 and later discharge standard.

The base material of traditional integral catalytic converter generally forms by extrusion molding.Past 25 years was used this not only complicated but also somewhat expensive method always.But there is restriction in extrusion molding.Still keep quality control restricted for producing how little passage in the material.Extrusion molding also makes the shape of catalytic converter be limited to cylinder or parallelogram or parallel sided in the shape of extruding axle.This shape restriction also is not a problem under the former discharge standard.But design can reach needs near the catalytic converter of zero-emission performance and particulate filter may require non-linear and/or the design of non-cylindrical filter and vehicle integrated.

Reduce wall thickness surface area is increased, for example some situation lower wall thickness is reduced to 0.002 inch from 0.006 inch and is made surface area increase by 54%.By increasing surface area, can in littler volume, deposit the more particles thing.Fig. 1 illustrates prior art formed honeycomb configuration 102 in the ceramic filter element 100 of constructing for the surface area that increases catalytic converter.Honeycomb configuration 102 usefulness extrusion moldings form, and wherein form the long-channel that main shaft is parallel to the effect of extruding.The opening surface of these passages is to the waste gas stream of input.

Along with development of technology, can make the ceramic cordierite substrates that wall thickness reduces.The standard configurations 400cpsi hole density and 0.0065 that in the past is used for passenger vehicle " (or about 0.17mm) 400/6.5 gradually by the more base material of thin-walled (0.0055 to 0.004mil) replacement.But the physics limit of approaching described material.Because the pottery physical characteristic of cordierite particularly, use by in addition more the base material made of the cordierite ceramic of thin-walled be unpractiaca.More the material of thin-walled can not satisfy other must characteristic (for example durability, hear resistance).

Diesel catalyst has the wall thicker than its automobile homologue usually, and partly cause is that its size is bigger.Because the diesel engine wall-flow filter generally has thicker wall, so the quantity of the passage per square inch that can have for these filters has physical restriction.In general, do not have per square inch and be purchased the diesel engine wall-flow filter more than 200 passages.

Another restriction that can get base material at present is its catalytic efficiency decline at a lower temperature.When converter system was in low temperature, for example during engine start, temperature is not high enough can not to begin catalytic reaction.Cordierite, carborundum and the various metal base sold at present with Corning, NGK, Denso and other company that adopt in the catalytic converter are to make with very tough and tensile, fine and close material, the mechanical strength of these materials and to the tolerance excellence of thermal shock and vibration.But these materials are from needing the time and absorb heat to reaching the temperature that is enough to carry out catalytic reaction after starting.Because the catalytic reaction start delay, estimate all about 50% being released in the atmosphere of discharging of in initial 25 seconds of engine running modern engine.Even the amount of pollutant that the little improvement in " cold start-up " these crucial several seconds can make annual success handle significantly improves.Though be devoted to head it off, but still need be able to be reduced in the catalytic converter of the discharging during this crucial cold start-up always.Even adopt most advanced and expensive technology at present, the cordierite-base catalytic converter starts also needs about 20 seconds.

In order to reach reaction temperature quickly, attempted mobile converter and made its more close enmgine exhaust, can reach higher temperature quickly and higher temperature also impels reaction more violent at manifold in operation process.Because free space is limited under the automobile hood, so converter system is size-constrained, thereby the throughput that can successfully handle is limited.Present base material can not use in the cabin of vehicle effectively.In addition, also not wishing increases extra weight to the cabin, and present many base material densifications and porosity limited (about 50% or lower), and handling large-scale capacity needs not only heavily but also huge system.And, for example base material of cordierite easily fusing under many operating conditions, thus result in blockage and back pressure is increased.

Other method of compensation cold start-up comprises the refining adsorption system of temporary transient storage NOx and/or hydrocarbon, thereby converter can be handled NOx and/or hydrocarbon once reaching critical-temperature.In these systems some need parallel pipeline and refining absorption surface, additional valve with controlling organization or be used to the different wash coat of multilayer that makes catalyst adhere to base material and isolate reaction environment.This problem is especially challenging in may needing to capture the Diesel engine of a large amount of soot particulates, NOx and SOx.In some big industrial diesel oil engines, utilize the diesel engine particles trap in a row of rotation to collect, store, handle then particle.(in other system, store NOx and be reduced into N at NOx ₂The time make CO change into CO used as oxidant ₂)

Consider regulatory limits, even can reduce easily that the system of some may not need more above-mentioned expensive and meticulous work in 50% discharging that takes place during the cold start-up total discharging.Use with these workspaces, this system can obviously reduce discharging.But as previously explained, traditional system is general complicated and expensive, also is tending towards making the missing of ignition and/or running instability of engine.

Another inherent limitations of legacy system is to burn particle required typical " time of staying ".When considering the big flow of combustion gas between on-stream period and flowing velocity that gas must reach, importantly converter can be lighted a fire rapidly.Therefore, can light a fire, can tolerate extreme heat and vibratory impulse rapidly and can run-up during cold start-up the catalytic converter of internal temperature will greatly strengthen the industrial ability that reduces discharging, satisfy upcoming 2007 and 2010 environmental standards, produce more automobile, truck, bus and the heavy duty industrial engine of clean operation.

If base material is also in light weight, then also will cause the mileage statistics of new car to be improved.But also do not find to solve the base material of a lot of or all these problems so far.

Catalytic converter or particulate filter are considered with the design of base material

Catalyst substrate is the vital component of the performance, intensity and the durability that influence catalyst system.In addition, filtering substrate also obviously influences the operating characteristics of particulate filter.Ideally, the base material that uses in catalytic converter or the particulate filter should have many attributes.These attributes are including but not limited to following one or more aspects: a) surface area; B) porosity/permeability; C) radiance; D) thermal conductivity; F) hot attribute such as resistance to sudden heating, thermal expansion and thermal conductivity; G) density; H) structural integrity; I) pollutant treatment effeciency; J) catalyst requirement; And k) weight of system.Catalysis or the filtering substrate of optimizing one or more attributes will be the progress of filtering fluid and field of catalytic reactions.

Summary of the invention

Various embodiments are described in the content of the present invention.These and other embodiment of the present invention is described in following detailed description part.

The present inventor finds that a kind of non-woven sintering refractory fibre pottery (nSiRF-C) composite (as described herein) can be used as and makes the improvement base material that is used for catalytic converter, particulate filter and relevant apparatus.

The present inventor also finds can be by improved catalyst substrates of the material preparation with specific properties described herein and improved filtering substrate.For example, the attribute of Shi Heing comprises the fusing point height, thermal conductivity is low, hot expansion system is low, ability is heated and vibratory impulse, density is low and porosity and permeability are very high.The examples material that has these attributes in a kind of embodiment is nSiRF-C.

An example with material of suitable attribute is the nSiRF-C composite.The example of nSiRF-C is thermal boundary (" AETB ") material or the similar material that aluminium oxide strengthens, and can be used as catalyst substrates or filtering substrate according to embodiment of the present invention.The AETB material is known in the art, comprises aluminium oxide boron oxide silica (being also referred to as aluminium oxide-boron oxide-silica, aluminoborosilicate and sial borate) fiber, silicon dioxide fibre and alumina fibre.A kind of known application of AETB be on space shuttle as the external application patch block, it is desirable being used for that space shuttle reentries.AETB is never as filtering substrate or substrate for catalytic converters.

The present inventor recognizes that the attribute that makes AETB be fit to aerospace industry also is preferred in combustion technology.AETB has the fusing point height, thermal conductivity is low, thermal coefficient of expansion is low, ability is heated and vibratory impulse, density is low and porosity and the very high attribute of permeability.Lack such combination of desirable attributes at present in filtration and the substrate for catalytic converters.

Also finding nSiRF-C composite such as AETB and similarly be fit to base material can preparation, moulding, mold pressing, cutting and/or mould (or other physical modification) and become the new model that is suitable as particulate filter and substrate for catalytic converters.

The present invention has many advantages that are better than present technology.At first, the present invention will cause air quality and respiratory health to improve.The present invention can significantly reduce the possibility of anthracemia.

Embodiment of the present invention can be used as the catalysis of present use and the direct substitute of filtering substrate and catalytic converter and particulate filter, exhaust and engine system.Describe in detail as the back, base material of the present invention provides the many advantages that are better than the prior art base material and has solved the still unsolved many problems of prior art base material.This can be converted into obvious saving cost for manufacturer.Because the present invention can be used as the direct substitute of present technology, need not redesign gas extraction system.Therefore, can only drop into not needing recombinant production factory and production line and obtain the waste gas filtering and the purification that strengthen under the situation of time seldom.

Improved catalysis of the present invention and filtering feature need to use less catalyst in certain embodiments.Because the catalyst that uses in the related application is very expensive mostly, this advantage also causes cost savings.

The preferred hot attribute of some embodiments of the present invention makes the needs for some parts of the gas extraction system that relates to the heat localization that present catalytic converter and particulate filter follow reduce and/or eliminates.May not need hot baffle and heat insulation in some embodiments of the present invention.Eliminating these assemblies from gas extraction system and vehicle directly (does not use assembly, thereby production cost is descended) and reduce cost indirectly (car weight reduces, thereby burning fee is reduced).Other benefit can comprise that performance is better, mileage number better and/or power is better.

In some embodiment, available littler but remove the identical or better catalytic converter of the present invention of efficient of pollutant or particulate filter replaces traditional catalytic converter or particulate filter.Catalytic converter or particulate filter are littler, and the free space as other purposes on the car is then bigger.And because filter of the present invention or converter are littler, the gross weight of vehicle alleviates.

Some embodiments of the present invention be to be applicable to all or part of catalyst substrates that is positioned at the catalytic converter of motor head on the other hand.Described catalytic converter (being called the front end catalytic converter herein) has the many advantages that are better than prior art.For example, owing to the restriction of present available catalyst substrates, this front end catalytic converter is unpractiaca traditionally.The acceptable substrate cordierite will absorb too many heat.Because the preferred thermal characteristics of base material of the present invention, the front end catalytic converter that comprises described base material will reduce the thermal stress of turbocharger and/or the last turbine of intercooler (if present).

The front end catalytic converter does not need the external hardware such as the hot baffle that add yet.Use the front end catalytic converter can keep engine and product as the preferred outward appearance in motorcycle.In some embodiment, use the front end catalytic converter also to reduce gas extraction system such as silencer and house steward's outside variable color.In some embodiment many attendant advantages of front end catalytic converter comprise following one or more: security improves; Filter otherwise intercooler with the particle of assembling, thereby improve the life-span of intercooler and save cost; Do not need bed course in some embodiment; Use the front end catalytic converter can reduce or eliminate the interior snapping sound of hot baffle; Can reduce the size of indispensable silencer with the front end catalytic converter.

In other embodiment of front end catalytic converter, more effectively burn the smaller particles thing.Under the situation of front end catalytic converter failure, only need change a little catalytic converter.The front end catalytic converter is returned ship, ship, motorcycle, fallen leaves purging machine etc. and is brought these advantages.

In addition, different embodiments of the present invention provides the following one or more advantages that are better than prior art: outward appearance is improved; Avoid using additional firmware; The present invention does not need additional firmware (because of managing tighter may the needs); Reduce or eliminate because of silencer and blast pipe variable color due to the heat-producing chemical reaction.The present invention can make base material littler in some embodiment, thereby makes silencer or jar in some system littler.Base material of the present invention resembles the as many heat of some traditional base material for the system that uses catalytic converter or particulate filter provides higher security because base material of the present invention has improved thermal property and do not absorb.And base material of the present invention cools off quickly than many traditional base materials, and security is improved.Certain embodiments of the invention provide improved heatproof degree variability, thereby seriously do not break, rupture or damage as some conventional base material when unexpected variations in temperature is arranged.In some embodiment, base material is than the easier manufacturing of conventional base material (for example nSiRF-C wall-flow type base material can be by the one piece material manufacturing not blocking channel).This attribute is not only saved time but also is saved money.

In other embodiment, nSiRF-C is more in light weight than conventional after-treatment device.This attribute is not only wanted for very heavy vehicle, and is also to be vital in the market (for example puffer, motorcycle, private ship, performance car) of influence factor in weight.

In some embodiment, base material of the present invention shows than the littler back pressure of competition after-treatment device.Back pressure is low can to cause vehicle performance raising, power to improve and the fuel economy raising.

Other embodiment of the present invention relates to the method for catalytic reaction for example, the method for filtering fluid, catalyst substrates preparation method, filtering substrate preparation method, by base material of described method preparation or the like, describe in detail as the back.

Description of drawings

Fig. 1 is the cutaway view with conventional cordierite substrates of honeycomb.In cordierite filters element 100, form honeycomb configuration 102.Honeycomb 102 usefulness extrusion moldings form, and wherein form the long-channel (or pipe) that main shaft is parallel to the effect of extruding.The opening surface of these passages is to the waste gas stream of input.During the emission admission passage, particle will be along the inner septum deposition of pipe.

Fig. 2 a and 2b illustrate the microphoto of cordierite sample.Among Fig. 2 b, the particle of ball 210 expression PM-10 sizes, the particle of ball 225 expression PM-2.5 sizes.

Fig. 3 is the ball 210 of cordierite 205 and expression PM10 particle and the microphoto of representing second ball 225 of PM2.5 particle.

Fig. 4 a is the longitudinal sectional view of typical catalytic converter schematic diagram.Catalytic converter 400 comprises reducing catalyst 402 and oxidation catalyst 404.When waste gas stream 406 entered catalytic converter 400, waste gas stream 406 was filtered and is exposed to reducing catalyst 402, is exposed to oxidation catalyst 404 again.Waste gas stream 406 is handled through oxidation catalyst 404 then, and unburned hydrocarbon and carbon monoxide are further burnt.

Fig. 4 b illustrates the schematic diagram of catalytic converter.

Fig. 5 is the cross-sectional schematic with three kinds of base materials of three kinds of different front face surface shapes.

Fig. 6 is the example schematic of the through-flow configuration of catalysis or filtering substrate.Base material has a plurality of passages 610 that formed by conduit wall 620.Fluid stream 630 enters front surface, leaves the rear surface by passage 610.

Fig. 7 is the example schematic of the wall stream configuration of catalysis or filtering substrate.The wall stream mode is made up of identical host material 720 and passage 710, except passage 710 not exclusively is communicated with the other end.Passage 710 forms as blind hole, stays the not boring part 740 of base material 720 in the end of passage 710.Fluid stream 730 passed through conduit wall 720 before leaving base material from the rear surface.A special benefits of the present invention is that wall flow pattern liquid stream 730 has and the essentially identical feature of through-flow type.

Fig. 8 is the example schematic of the wall stream configuration of catalysis or filtering substrate.In the case, fluid stream 830 enters base material from front surface.Some fluids flow through the part 845 of not holing and leave base material from the rear surface.

Fig. 9 is the end-view of embodiment that adopts the base material 900 of wall circulation road.The part 920 of not holing in inlet or exit of passage alternately.Drilled tunnel 910 replaces with the not boring part 920 of the passage of holing from opposition side.As a result, as if base material has " chessboard " type passage.

Figure 10 a-10d illustrates the contrast of front face surface long-pending 1020,1021,1022,1023, and the contrast of the quantity in hole 1010,1011,1012,1013 is shown.Comparison diagram 10a and 10c, each embodiment all has identical hole density, the i.e. quantity in passage or hole.But the front face surface of Figure 10 c is long-pending much higher.Thereby it is desirable to make the long-pending minimum structural intergrity that still keeps of front face surface.Can between the embodiment of Figure 10 b and 10d, similarly contrast.With regard to Figure 10 a-10d, the embodiment of Figure 10 b has preferred construction; Hole density maximization and front face surface are amassed and are minimized.

Figure 11 is shown to scale the embodiment of square passageway.In this embodiment, hole 1110 is 31.83: 1.5 with the ratio of hole wall 1120, or about 20: 1.

Figure 12 illustrates the embodiment that has in proportion the example hole that shows and the base material 1210 of hole wall ratio.Base material 1210 is long * wide be 4 square inches, comprise four 1/8 inch * 1/8 inch square 1220,1221,1222,1223.Thereby each of four squares 1220,1221,1222,1223 is all holed and is had 900 hole density, and the hole density of total base material is 3600.Wall thickness is 1.5 mils between the Kong Yukong.Spacing on the base material 1210 between each square 1220,1221,1222,1223 is 7/8 inch, square 1220,1221,1222,1223 apart from the nearest edge of base material 1210 all about 7/16 inch.

Figure 13 a-c illustrates several embodiments of channel design.Figure 13 a-13c illustrates hexagonal channel 1310, triangular duct 1320 and square passageway 1330 respectively.These embodiments are all successfully implemented the present invention, because the wall 1315,1325,1335 of passage 1310,1320,1330 is parallel to each other basically.

Figure 14 illustrates embodiment of the present invention.This microgram illustrates the similar substantially size of rectangular channel 1410,1411,1412,1413 in the base material 1415,1416,1417,1417.The fiber 1420,1421 that exists in Figure 14 c and the 14d illustrative material.These fibers demonstrate porosity, and it is better than the cordierite platelet in the conventional system.

Figure 15 is the X-Y scheme of spendable comb 1500 in the comb platen press of preparation catalysis of the present invention or filtering substrate.

Figure 16 illustrates the various views of spendable comb 1600 (or its part) in the certain embodiments of the invention.Figure 16 also provides the typical physical size (inch) of comb 1600.

Figure 17 is surface area enhancing that can form in the filter element of embodiment of the present invention and the schematic diagram of importing and exporting pipe.Figure 17 provides the fluid stream 1704 from front surface admission passage opening 1702.Fluid leaves the rear surface of base material at right-hand side 1704.Base material shown in Figure 17 illustrates the base material with wall stream configuration, wherein extends to channel end along with passage passes base material from access portal, and channel size reduces gradually.

Figure 18 is the longtitudinal view (photo) of base material embodiment of the present invention.Filter base material 1800 of the present invention is shown.On the outer wall 1802 of base material 1800 hard conating 1804 is arranged.For sample shown in Figure 18, hard conating is made up of cordierite in small, broken bits and inorfil.Powder also is applied on the filter base 1800 and curing as described herein.Hard conating protection and guard filter substrate and not varying sized.

Figure 19 is the diagram of the required time of staying of combustion particle thing under different temperatures.Provide and burn at various temperatures or burn particle (cigarette ash material) the required time of staying.As seen, burning or time of staying of burning the cigarette ash material that 0.9 cigarette ash material is arranged at first are more much longer than the time of staying under 1200K under 600K.

Figure 20 illustrates exhaust substrate system 2000, comprises the base material 2002 with 2004 combinations of silk screen heating element heater.Base material 2002 and silk screen heating element heater 2004 flow in the angled insertion blast pipe 2006 with respect to waste gas.Because angle causes that silk screen heating element heater 2004 places base material 2002 rears and below, the more effective and uniform heating base material 2002 of principle that can utilize known heat to rise.As previously described, more even and also effectively heating base material 2002 can be burnt more completely or flash off particle, exhaust is more cleaned.

Figure 21 is description and the filter element 2102 of discussion and the front view of silk screen heating element heater 2104 relevant with Fig. 9.As seen, thus filter element 2102 and silk screen heating element heater 2104 are oval-shapedly to be assemblied in the pipe at a certain angle.The type of the shape of the shape of blast pipe, filter element 2102, heating element heater 2104 and angle all can change the requirement and the restriction of using with the gas extraction system that is fit to expection.

Figure 22 a is the microphoto of base material of the present invention (AETB particularly).

Figure 22 b is the microphoto of base material of the present invention (AETB particularly).Can see fiber 2205.The particle of ball 2210 expression PM-10 sizes, the particle of ball 2225 expression PM-2.5 sizes.

Figure 23 is pressure drop (Δ P) that seven kinds of test materials the are shown hourly space velocity (hr as gas ^-1) the figure of function: Corning 200/12 DPT 932F (2340); The AETB-11 (2310) of 600cpsi, 6mil wall thickness and 11lb/ft, 1100F; 600cpsi, 6mil wall thickness and 11lb/ft ³, 932F AETB-11 (2320); 600cpsi, 6mil wall thickness and 11lb/ft ³, 662F AETB-11 (2330); The cordierite of 1100F (2350); The cordierite of 932F (2360); Cordierite (2370) with 662F.

Figure 24 is that the % destructive rate is with the variation of temperature curve map.Base material 2410 of the present invention shows the destructive rate of at a lower temperature the material bigger than cordierite substrates 2420.

Figure 25 is the cutaway view that the present invention improves the embodiment of catalytic converter.In this embodiment, catalytic converter comprises durable and heat-resisting pipe 2502.Pipe 2502 has inlet 2504 and air exit 2506.Improve base material 2510 one or more districts 2512,2514 are arranged.Improvement base material 2510 is wrapped or is encapsulated in one or more bed course/insulating barriers 2515.Bed course 2515 can be applied on the filter base 2510 2510 avoiding the vibratory impulse of engine and mobile environment at the bottom of the protecting group, and the interior hot temperature isolation that makes external environment condition and filter base 2510.

Figure 26 has the catalytic converter of four base material 2601a, 2601b, 2601c and 2601d being arranged in parallel or the schematic diagram of particulate filter 2600.Filter or converter have open front 2604 and back outlet 2605.

Figure 27 a-c illustrates catalytic converter or the particulate filter 2700 with stacked film configuration base material 2710.Inlet 2720 and outlet 2730 designs are at differing heights.Figure 27 b and 27c illustrate optional embodiment.

Detailed Description Of The Invention

Summary

In certain embodiments, the present invention relates to be applicable to the catalyst substrates of many application, be included in and make base material in the catalytic converter. Another aspect of the present invention relates to the filtering substrate that is applicable to many application, is included in particulate filter such as diesel particulate filter (DPF) or the diesel engine particles trap (DPT) and makes base material. The present invention also is provided for removing and/or the improvement base material of destroy contaminants from the waste gas of combustion machine. In certain embodiments, described catalyst substrates and filtering substrate provide improvement remove pollutant from waste gas aspect. Described improvement include but not limited to following one or more: light-off period is shorter, the in-depth filtration of PM increases, back pressure reduces, blocking probability descends, and places the interior a plurality of positions of gas extraction system to comprise that the ability of manifold or exhaust head itself increases, and the possibility of catalytic reaction is high, the conversion ratio of NOx, HC and CO is high, burn quickly PM, the minimized of catalyst material, and the weight saving of post processing gas extraction system etc.

Other embodiment of the present invention comprises catalytic converter, particulate filter, diesel particulate filter and diesel engine particles trap etc. The present invention also provides manufacturing or the preparation method of catalysis and filtration base material, catalytic converter, particulate filter, catalytic muffler and gas extraction system. Other embodiment of the present invention comprises pre-catalytic converter, rear catalytic converter, front end catalytic converter and manifold catalytic converter, and each in these catalytic converters comprises base material of the present invention. In addition, in optional embodiment, the present invention relates to the base material by the methods described herein preparation.

On the other hand, one or more catalyst substrates or the filtering substrate that provides in the following attribute is provided: light-off period is shorter, the in-depth filtration of PM increases, back pressure reduces, blocking probability descends, can place the interior a plurality of positions of gas extraction system to comprise manifold or exhaust head itself, the possibility of catalytic reaction is higher, the conversion ratio of pollutant such as NOx, HC and CO is higher, burn quickly PM, the outside wall temperature reduction of faster and base material etc. of lighting a fire when the consumption minimizing of required catalyst material, cold start-up.

Use base material of the present invention, catalytic converter, particulate filter or gas extraction system that many advantage and improvement that are better than prior art are provided. In some embodiment, these improved catalytic converters and/or particulate filter can be removed and/or destroy contaminants from the waste gas of combustion machine, have many special advantages, such as the back more detailed description. Improved gas extraction system be equally invention described herein on the other hand. Improved gas extraction system reduces the amount of the pollutant of running engine discharge.

Be described in more detail below the present invention, comprise non-limiting embodiments and embodiment. Embodiment that this paper discusses only is used for illustrating. The invention is not restricted to these embodiments.

Catalyst substrates

The present invention relates to a kind of catalyst substrates, it comprise non-woven sintering refractory fibre described herein pottery (nSiRF-C) composite (alternatively consisting of or mainly consisting of), described catalyst substrates can be used for catalytic converter, particulate filter and relevant apparatus; The catalyst such as the catalytic metal that also comprise alternatively effective dose. The preferred catalytic base material comprises catalyst. The nSiRF-C composite can be made into the configuration that is fit to purposes described herein.

NSiRF-C composite right and wrong are woven. In some embodiment, the nSiRF-C composite is the material with definite rigid three-dimensional shape. The fiber of nSiRF-C composite is not with organized pattern arrangement, but with the mode three-dimensional arrangement of random, accidental or omnidirectional. In some embodiment, described nSiRF-C is matrix form.

NSiRF-C is the composite of sintering. In a kind of embodiment, the composite of sintering is the bonding material that adds thermosetting in infusible situation. But the method for sintered ceramic material is well known in the art, and therefore scope of the present invention is not necessarily limited to specific embodiments as herein described and specification. Sintering forms cohesive body and remaining without resin. According to the present invention, sintered ceramic is the bonding material of the formed loosen collagen fibre of heating in infusible situation.

NSiRF-C is the refractory fibre ceramic composite. The nSiRF-C of some embodiment is comprised of different length and the senior refractory fibre that forms, as cited in the non-limiting embodiments herein.

In a kind of embodiment, the present invention relates to a kind of catalyst substrates that is applicable to many application described herein. This base material comprises the many materials with one or more attributes, preferably has multiple attribute described herein. Base material of the present invention is made by non-woven fiber ceramics composite, and described composite is made by fire-resistant level fiber. This material is disclosed in US 4,148, and in 962, it is incorporated herein for reference in full. Other material that is fit to is disclosed in US 3,953, in 083.

In a kind of embodiment, catalyst substrates of the present invention comprise (alternatively consisting of or mainly consisting of) aluminium oxide thermal boundary (" the AETB ") material or the similar material known to persons of ordinary skill in the art that strengthen. The AETB material is known in the art, be described in more fully Leiser etc., " Options for Improving Rigidized Ceramic Heatshields ", Ceramic Engineering and Science Proceedings, 6, No.7-8, pp.757-768 (1985) and Leiser etc., " Effect of Fiber Size and Composition on Mechanical and Thermal Properties of Low Density Ceramic Composite Insulation Materials ", NASA CP 2357, among the pp.231-244 (1984), these two pieces of documents all are incorporated herein for reference.

In another embodiment, catalyst substrates comprises ceramic tile, for example has the thermal boundary (AETB) of the aluminium oxide enhancing of toughness reinforcing monolithic fibrous insulation (TUFI) and/or reaction curing glass (RCG) coating. These materials are known in the art.

The another kind of material that is fit to is fibre fire-proof ceramic insulation (FRCI). In a kind of embodiment, AETB is made by aluminium oxide boron oxide silica (being also referred to as aluminium oxide-boron oxide-silica, aluminoborosilicate and sial borate) fiber, silicon dioxide fibre and alumina fibre. A kind of known application of AETB be on space shuttle as the external application patch block, it is desirable being used for that space shuttle reentries. AETB has the fusing point height, thermal conductivity is low, thermal coefficient of expansion is low, ability is heated and vibratory impulse, density is low and porosity and the very high attribute of permeability. Therefore, in a kind of preferred embodiment, the fusing point of catalyst substrates is high, thermal conductivity is low, hot expansion system is low, ability is heated and vibratory impulse, density is low, porosity is high and permeability high.

In a kind of embodiment, the first component of AETB is alumina fibre. In the preferred version of the present invention, aluminium oxide (Al₂O ₃Or alundum (Al2O3), for example SAFFIL) typical case is purchased about 95-about 97 heavy % aluminium oxide of form and the about 5 weight % silica of about 3-. In other embodiment, more the aluminium oxide of low-purity is also applicable, and for example 90%, 92% and 94%. In other embodiment, more highly purified aluminium oxide is also applicable. Aluminium oxide can be by extruding or reel off raw silk from cocoons method production. At first, preparation precursor solution. Cause slow and progressive polymerization process, for example by control pH, thereby single precursor molecule is in conjunction with forming larger molecule. Along with the carrying out of this process, mean molecule quantity/size increases, thereby causes solution viscosity to increase in time. Under the viscosity of about 10 centipoises, solution becomes gets slightly gluing, can draw or reels off raw silk from cocoons fiber. Under this state, also can extrude fiber by die head. In some embodiment, fiber diameter is in the about 6 microns scope of about 1-, but fiber larger and more minor diameter also is applicable to the present invention. For example, in other embodiment fibre diameter at 1-50 micron, preferred 1-25 micron, more preferably in the scope of 1-10 micron.

In a kind of embodiment, the second component of AETB is silicon dioxide fibre. In some embodiment, silica (SiO₂, for example Q-fiber or quartz fibre) comprise and surpass 99.5 heavy % amorphous silicas, impurity content is very low. More the silica of low-purity (for example 90%, 95% and 97%) also is applicable to the present invention. In some embodiment, use amorphous silica, the low (2.1-2.2g/cm for example of its density³), heat resistance high (1600 ℃), thermal conductivity low (about 0.1W/m-K) and thermal expansion approach zero.

In a kind of embodiment, the 3rd component of AETB is aluminium oxide boron oxide silicon dioxide fibre. In some situation, aluminium oxide boron oxide silicon dioxide fibre (3Al₂O ₃·2SiO ₂·B ₂O ₃, for example NEXTEL 312) normally 62.5 heavy % aluminium oxide, 24.5 heavy % silica and 13 weigh the % boron oxides. Certainly, the definite percentage of the composition of aluminium oxide boron oxide silica can change. It mainly is amorphous products, but can contain the crystallization mullite. Aluminium oxide boron oxide silicon dioxide fibre that is fit to and preparation method thereof for example is disclosed among the US 3,795,524, and its instruction all is incorporated herein for reference.

The material that another kind is suitable as base material of the present invention comprises can be from Orbital pottery (Valencia, CA) the Orbital ceramic thermal barrier material (OCTB) of Huo Deing.

Other material that is suitable for use in the present invention as nSiRF-C comprises AETB-12, and (it consists of about 20%Al ₂O ₃, about 12% (14%B ₂O ₃, 72%Al ₂O ₃, 14%SiO ₂NEXTEL ^TMFiber) and about 68%SiO ₂); (it consists of about 20%Al to AETB-8 ₂O ₃, about 12% (14%B ₂O ₃, 72%Al ₂O ₃, 14%SiO ₂NEXTEL ^TMFiber), 68%SiO ₂); (it consists of about 78wt.% silica (SiO to FRCI-12 ₂) and 22wt.% aluminoborosilicate (62%Al ₂O ₃, 24%SiO ₂, 14%B ₂O ₃)); And FRCI-20 (it consists of about 78wt.% silica (SiO ₂) and about 22wt.% aluminoborosilicate (62%Al ₂O ₃, 24%SiO ₂, 14%B ₂O ₃)).

In a kind of preferred embodiment, the inorfil component by or mainly fibrous by fiber silica, alumina fibre and aluminoborosilicate.In this embodiment, about 50-90% of fiber silica comprises inorfil mixture, alumina fibre accounts for about 5-50% of inorfil, and the aluminoborosilicate fiber accounts for about 10-25% of inorfil mixture.In some embodiment, preparing the used fiber of base material of the present invention can existing crystalline phase have glassy phase again.

Other fiber that is fit to comprises the aluminoborosilicate fiber, its preferably be contained in the aluminium oxide of about 55wt% to about 75wt% scope, less than about 45wt% to greater than the silica in 0wt% (preferably less than 44wt% extremely greater than the 0wt%) scope and less than 25wt% extremely greater than the boron oxide in 0wt% (preferably about 1wt% the is about 5wt% extremely) scope (respectively based on Al ₂O ₃, SiO ₂, and B ₂O ₃Theoretical oxide calculate).The aluminoborosilicate fiber is 50wt% crystal at least preferably, more preferably 75wt%, 100wt% (being crystal fibre) most preferably from about at least.The aluminoborosilicate fiber of grading is commercially available, for example with trade name " NEXTEL 312 " and " NEXTEL 440 " available from 3M Company.In addition, the aluminoborosilicate fiber that is fit to can be as US 3,795, disclosed preparation in 524, and it all is incorporated herein for reference.

Other fiber that is fit to comprises aluminosilicate fiber, normally crystallization, its be included in about 67wt% to about 77wt% (for example 69wt%, 71wt%, 73wt% and 75wt%) scope aluminium oxide and at about 33wt% silica in about 23wt% (for example 31wt%, 29wt%, 27wt% and the 25wt%) scope extremely.The aluminosilicate fiber of grading is commercially available, for example with trade name " NEXTEL 550 " available from 3M Company.In addition, the aluminosilicate fiber that is fit to can be as US 4,047, disclosed preparation among 965 (Karst etc.), and its disclosure is incorporated herein for reference.

In other embodiment, prepare the used fiber of base material of the present invention and comprise and be added with Y ₂O ₃And ZrO ₂α-Al ₂O ₃, and/or add SiO ₂α-Al ₂O ₃(form α-Al ₂O ₃/ mullite).

Available various special material prepares catalyst substrates.In a kind of embodiment, prepare base material material therefor of the present invention and comprise (or form or mainly form by it alternatively) fire-resistant silicon dioxide fibre and fire-resistant boron sikicate aluminum fiber by it.In another embodiment, preparation catalyst substrates material therefor comprises fire-resistant silicon dioxide fibre, fire-resistant grade aluminum oxide fiber and adhesive, preferred boron oxide or boron nitride powder.In another embodiment, fiber is senior.

In another embodiment, described base material comprises refractory composite, and described refractory composite mainly is made up of at aluminosilicate fiber and silicon dioxide fibre in about 19: 1 to 1: 19 scopes weight ratio; With about 0.5% to 30% boron oxide, based on total weight of fibers.Perhaps, the weight ratio of aluminosilicate fiber and silicon dioxide fibre be selected from 16: 1,14: 1,12: 1,10: 1,8: 1,6: 1,4: 1,2: 1,1: 1,1: 2,1: 4,1: 6,1: 8,1: 10,1: 12,1: 14 and 1: 16.In other embodiment, the amount of boron oxide is about 5%, 10%, 15%, 20%, 25% or 30%.In another embodiment, boron oxide and aluminosilicate fiber exist with the aluminoborosilicate fibers form.In another embodiment, catalyst substrates comprises the nSiRF-C composite, and wherein aluminosilicate fiber and the ratio of silicon dioxide fibre are in 1: 9 to 2: 3 scope, and boron oxide content is about 1% to 6% of a fibre weight.

In another embodiment, be applicable to that the fiber of preparation base material of the present invention comprises the refractory fibre that 3M produces, as NEXTEL ^TMCeramic Fiber 312, NEXTEL ^TMCeramic Fiber 440, NEXTEL ^TMCeramic Fiber 550, NEXTEL ^TMCeramic Fiber 610 and NEXTEL ^TMCeramic Fiber 720.Composite level fiber Nextel ^TMFibers 610,650 and 720 has based on α-Al ₂O ₃More refining crystal structure and do not contain any glassy phase.This makes it to keep intensity under higher temperature.Nextel ^TMFiber 610 has α-Al basically ₂O ₃Single-phase composite.Even at room temperature start from maximum intensity, its strength retention under heating up is also minimum.Nextel ^TM(it is to be added with Y to Fiber 650 ₂O ₃And ZrO ₂α-Al ₂O ₃) and Nextel ^TM(it is to add SiO to Fiber 720 ₂α-Al ₂O ₃(form α-Al ₂O ₃/ mullite)) strength retention under heating up is better and creep is littler.

In the another kind of embodiment that is fit to, nSiRF-C is made by ceramic fibre or comprises (or formed or mainly be made up of it by it alternatively) ceramic fibre, and described ceramic fibre comprises Al ₂O ₃, SiO ₂, and B ₂O ₃, have following attribute: 1) fusing point is about 1600 ℃ to about 2000 ℃, preferred about 1800 ℃; 2) density is extremely about 4g/cc of about 2g/cc, and preferably about 2.7g/cc is to about 3g/cc; 3) refractive index is about 1.5 to about 1.8, more preferably is selected from 1.56,1.60,1.61,1.67 and 1.74; 4) monofilament tensile strength (25.4mm specification) is about 100MPa about 3500MPa extremely, and more preferably from about 150 to about 200 or about 2000 to about 3000, or be selected from 150,190,193,2100 or 3100; 5) thermal expansion (100-1100 ℃) is about 2 to about 10, and preferred about 3 to about 9, more preferably is selected from 3,4,5.3,6 and 8; With 6) surface area is less than about 0.4m ²/ g, be more preferably less than about 0.2m ²/ g.In other embodiment, the crystalline phase of fiber is a mullite and amorphous, essentially no setting, γ-Al ₂O ₃Or amorphous Si O ₂In other embodiment, the dielectric constant of fiber that is applicable to preparation base material of the present invention is about 5 to about 9 (under 9.375GHz), or is preferably selected from 5.2,5.4,5.6,5.7,5.8,6,7,8 and 9.

In some embodiment, base material of the present invention is " no solids " basically, means the particulate ceramic (being crystalline ceramics, glass or glass ceramics) that does not contain from fiber manufacture process.

In some embodiment, the nSiRF-C composite is " rigidity ".In a kind of embodiment, it is can not be more crooked more and do not rupture, break or the base material of permanent deformation or deformity that rigidity has meant 1,2,3,4,5,6,7,8,9,10,15,20 or 25 degree angles (with respect to bending point).

The diameter of used fiber may be different in the different embodiments of the present invention.In some embodiment, average diameter is about 1 micron to about 50 microns, preferred 1 micron to about 20 microns.In other embodiment, average diameter is about 6,7,8,9,10,11,12,13,14 or 15 microns.In other embodiment, the fiber diameter of aluminium oxide boron oxide silicon dioxide fibre is about 10 microns to about 12 microns.

In another embodiment, catalyst substrates of the present invention also comprises adhesive such as boron nitride.In another embodiment of the present invention, when not using aluminium oxide boron oxide silica, add boron nitride and replace aluminium oxide boron oxide silicon dioxide fibre.That is, in some embodiment, base material comprises silicon dioxide fibre, alumina fibre and the boron nitride of (or formed or mainly it be made of or by it made by it) and similar weight percent noted earlier.In another embodiment, base material comprises silicon dioxide fibre, alumina fibre and boron adhesive.In some embodiment, each in these all can contain a spot of other material such as organic adhesive, inorganic bond and some fibre or non-fiber impurity.In other embodiment, base material does not contain organic adhesive.And, under other situation, to make the nSiRF-C adhesive therefor and in process for making, change on the material, this is known in this area.

Other material that is applicable to preparation base material of the present invention is disclosed in US 5,629, and in 186, the low-density of wherein having described by amorphous silica and/or alumina fibre and the boron nitride preparation that accounts for fibre weight 2-12% fuses the fiber ceramics composite.In another embodiment, add thickener.The thickener that is fit to is known in the art.

In other embodiment, the average tensile strength of preparation nSiRF-C used ceramic fibre greater than about 700MPa (100,000psi), be preferably greater than about 1200MPa (200,000psi), more preferably greater than about 1800MPa (300,000psi), most preferably greater than about 2100MPa (350,000psi).

In another embodiment, add dispersant.The dispersant that is fit to is known in the art.

In other embodiment, catalyst substrates is through processing aspect one or more, change, modification and/or strengthen, and is as described herein and/or known in the art.

In other the embodiment, there is the trace impurity in various sources again.Under these situations, described impurity does not influence nSiRF-C and/or its attribute basically.

Base material of the present invention does not comprise NEXTEL ^TMWoven fabric or pad.

Catalyst

On the other hand, the present invention relates to comprise the base material as mentioned above of catalyst.Many catalyst all can make with base material and be used for forming catalyst substrates.Catalyst can be coated on the substrate surface.That is, in a kind of embodiment, catalyst is adsorbed on the surface (for example conduit wall) of catalyst substrates.Catalyst also can be present in the in-core of base material and be attached to each fiber of base material.In some embodiment, the present invention can play identical with present technology or better act on and need the catalyst of less amount.

In another embodiment, catalyst only is deposited on the conduit wall surface and is not deposited on conduit wall inside.In another embodiment, catalyst deposit is on the access road wall, on the exit passageway wall, in the wall or their combination.In another embodiment, first catalyst embeds the initial or neighbouring part of (line), coating or infiltration lane wall again; The middle part of the second catalyst embedding, coating or infiltration lane wall; And the 3rd catalyst is in the end portion of conduit wall.

In a kind of embodiment, catalyst substrates of the present invention preferably contains catalytic metal.In another embodiment, catalyst substrates does not contain catalytic metal.But under certain conditions, base material can be under the situation that does not need independent catalytic metal the catalysis appropriate reaction, for example in some embodiment, wash coat as hereinafter described can play catalyst action.

Can use any catalyst that can be applied to base material.Such catalyst includes but not limited to that platinum, palladium (as palladium oxide), rhodium, their derivative comprise oxide, and their mixture.In addition, catalyst is not limited to noble metal, noble metal combination or only limits to oxidation catalyst.Other catalyst that is fit to comprise chromium, nickel, rhenium, ruthenium, silver, osmium, iridium, platinum and gold, they derivative, reach their mixture.Other catalyst that is fit to comprises the economic benefits and social benefits oxide of palladium and rare earth metal, and as US 5,378, disclosed in 142 and 5,102,639, disclosure all is incorporated herein for reference.These economic benefits and social benefits oxides can be produced by the solid-state reaction of palladium oxide and rare-earth oxide, for example produce Sm ₄PdO ₇, Nd ₄PdO ₇, Pr ₄PdO ₇Or La ₄PdO ₇Can be used for other catalyst of the present invention and comprise US 6,090, those disclosed in 744 (the transferring Mazda MotorCorporation).Other catalyst that is fit to comprises non-metallic catalyst, organic catalyst, base metal catalysts and noble metal catalyst.

Other catalyst that is fit to is disclosed in 6,692, in 712 (the transferring Johnson MattheyPublic Limited Company).Can use the catalyst that does not comprise noble metal among the present invention.This catalyst is shown in US 5,182, in 249.

(consumption is about 5-150g/ft to the platinum catalyst that the another kind of Engelhard exploitation is fit to by the Pt/Rh of 5: 1 ratios ³) and MgO (consumption is about 30-1500g/ft ³) constitute.

In other embodiment, vanadium and derivative thereof be V for example ₂O ₅Be the catalyst that is fit to, especially for diesel particulate filter.This catalyst obtains and has been used for diesel particulate filter commercial.

Developed and utilized V ₂O ₅Vfanadium compound in addition is the catalyst of vanadic acid silver or vanadic acid copper for example.Heraeus (Strutz 1989) has developed an example of vanadic acid copper base metal catalysts.This catalyst can be by with Cu: V: about 3: 2: 0.13 of K mol ratio is with vanadic acid copper Cu ₃V ₂O ₈Prepare with potash doping and calcining.Catalyst load is 10 and 80g/m ²Between the filter table area.The another kind of catalyst that is fit to is Cu/ZSM5, and it can be used as denitrogenation oxidation (DeNox) catalyst.

Noble metal such as platinum, palladium and rhodium are the most frequently used and preferred, but other catalyst known in the art also can use.Excellence and effective catalyst that known these three kinds of noble metals are engine exhaust things.Catalytic converter more than 25 years in, still do not have the substitute of real significant this triple.But thousands of kinds of combinations of these catalyst have been disposed according to original device producer, vehicle, vehicle load, environmental management, engine, transmission device etc.Whole truck and auto manufacturing adopt the combination and the prescription of various catalyst.Catalyst substrates of the present invention comprise in these catalyst combination any one or multiple.Many combinations are considered as proprietary material.There is the unique catalyst prescription at every money car in manufacturers such as Ford, GM and Toyota, because car weight is different with the engine performance demand.Manufacturer also will sell or obtain the place of license according to vehicle, for example Canada, the U.S., California, Mexico are at a car different catalyst formulations being arranged.At present, these every money car per car type years of filling a prescription may change two to three times, because the governability strictness.For this reason, most manufacturers oneself grasp the application of catalyst coatings.

In another embodiment, catalyst substrates comprises the catalyst that uses in nSiRF-C and the commercial catalytic environment that can get.

On the one hand, base material is molded to reach that its final size and wash coat have applied and when solidifying, use one or more catalyst with known technology and method, as US 5,224,852 and 5,272, the method of application of disclosed palladium-platinum based catalyst in 125, its instruction all is incorporated herein for reference.

In a kind of embodiment, the amount of catalyst is enough to carry out effectively catalytic reaction.For example, in a kind of embodiment, the emission that capacity means in the amount of emission path and the interactional catalyst of emission (for example noble metal) enough and many as far as possible (for example 80%, 85%, 90%, 95%, 97%, 98% and 99% etc.) reacts.

In a kind of embodiment, catalyst deposit is on wash coat or be impregnated in the wash coat, preferably with single crystal form.In this embodiment, catalyst is not to be coated on (as the coating on the wall) on the wash coat as the top layer type coating.And when catalyst soakage was on wash coat, applications catalyst made finished product part or be the colony of single crystal basically.This can be envisioned as the salt crystal on the spiced salt cracknel.Enough intervals are preferably arranged between catalyst.Simultaneously, for example in the exhaust pathway enough noble metals should be arranged, be in the best catalytic activity operating temperature and promptly light a fire, and described noble metal must be to cooperate in the space in the physical restriction of vehicle and the duty of engine and design permission at fluid path.

Productive target is to make the pollutant of removing make the amount minimum of required catalyst on the base material at most.The contaminant capacity difference that every money car produces, so base material will be for tackling amount of pollutant and the noble metal amount minimum being customized in some embodiment.

In another embodiment, can in the slurry process process, catalyst be added in the catalyst substrates during base material, perhaps can be after processing technology catalyst be added (as hereinafter described) in the catalyst substrates in preparation.In the case, before any heating steps, catalyst is mixed with fiber slurry.

Can on single base material, use single and the multi-catalyst prescription, perhaps, can arrange a plurality of base materials owing to filter size for existing catalytic converter and gas extraction system is little.Therefore, in a kind of embodiment, catalyst substrates of the present invention comprises one or more districts or is formed or mainly be made up of it by it, and wherein there is different catalyst in each district.Perhaps, one or more districts can be by catalysis.For example, catalyst substrates of the present invention can comprise the oxidation catalyst that is positioned at a district that comprises the base material front surface and be positioned at another reducing catalyst distinguished that comprises the rear surface.

If described base material will use with through-flow configuration, then preferred (but be not must) catalyst or most of catalyst exist along channel surface.If base material processing wall-forming stream configuration, then preferred catalyst evenly distributes in whole base material, because all parts that gas will be by base material but not only pass through base material.

For example, base material of the present invention can be used for catalyzed diesel particulate filter (CDPF).CDPF utilizes the catalyst that directly is deposited on the base material.Expensive and base metal catalysts all can use, for example platinum, silver, copper, vanadium, iron, molybdenum, manganese, chromium, nickel and their derivative (as oxide) or the like.Depend on filter type, but the catalyst direct impregnation in medium or can use in the middle of wash coat.CDPF can utilize about 325-420 ℃ delivery temperature regeneration, depends on engine technology (PM discharging) and fuel mass (sulfur content).

Platinum is one of high and the most the most frequently used active noble metal catalyst, but palladium, rhodium or ruthenium catalyst (being generally mixture) also are applicable to the present invention.The non-platinum group metal that is usually used in catalytic converter comprises vanadium, magnesium, calcium, strontium, barium, copper and silver.In a kind of embodiment, platinum is the preferred catalyst that uses with Diesel engine.In another embodiment, palladium and rhodium are fit to use with petrol engine.

Catalyst is quite expensive usually.Thereby expectation reaches maximum pollution reduction with minimum catalyst amount.Platinum and palladium (two kinds of catalyst commonly used) all are very expensive noble metals.Have the big base material of porous permeability and surface area and can reach this target, wherein catalyst can equally distributed crystal or a layer form be present on the base material.Advantage of the present invention is that the catalyst requirement is lower than traditional base material.

Nineteen nineties cross-country engine with typical platinum load in the filter at 35g/ft ³And 50g/ft ³Between.These filters are installed in and pollute on the higher engine, need nearly 400 ℃ minimum temperature to regenerate.Afterwards, when the city bus that catalytic filter is used to clean manyly and the engine of other highway communication instrument, the discovery catalytic filter can be regenerated under much lower temperature.But need higher platinum load to support low-temp recovery.The platinum load of filter device therefor is generally 50-75g/ft in the cleaning engine cryogenic applications ³

In a kind of embodiment, catalyst substrates comprises about 1g/ft ³To about 100g/ft ³, about 1g/ft ³To about 50g/ft ³, about 1g/ft ³To about 30g/ft ³, or about 10g/ft ³To about 40g/ft ³Catalyst.

In another embodiment, the preferred nSiRF-C of catalyst substrates such as AETB, OCTB and FRCI comprise about 5: 1 of ratio and the about 30g/ft of content ³Platinum and rhodium catalyst.

Filtering substrate

The present invention relates to a kind of catalyst substrates, it comprises non-woven sintering refractory fibre pottery (nSiRF-C) composite (as described herein), can be used for particulate filter and relevant apparatus.Described filtering substrate is made and is applicable to filtration, especially for special shape, design, size and the configuration of filtration of particulate matters.Filtering substrate is specially adapted to filtration of particulate matters under extreme condition (temperature, pressure etc.), flows as filtering exhaust.Filtering substrate can be used for other application that needs filter small particle.

In a kind of embodiment, filtering substrate comprises that the front is at the described nSiRF-C composite of catalyst substrates (perhaps formed or mainly be made up of it by it alternatively).Filtering substrate does not comprise catalyst.All changes, embodiment and the example of material that is suitable as the base material of catalyst substrates is equally applicable to filtering substrate of the present invention.

Filtering substrate is made the configuration that is fit to application described herein, especially for grain catcher such as diesel engine particles trap and diesel particulate filter.

In a kind of embodiment, filtering substrate of the present invention is thermal boundary (" AETB ") material or the known similar material of those of ordinary skills that aluminium oxide strengthens.AETB is made by aluminium oxide boron oxide silica (being also referred to as aluminium oxide-boron oxide-silica, aluminoborosilicate and sial borate) fiber, silicon dioxide fibre and alumina fibre.A kind of known application of AETB be on space shuttle as the external application patch block, it is desirable being used for that space shuttle reentries.Make AETB unique and also be preferred in the organic combustion technology for the very desirable attribute of aerospace industry.AETB has the fusing point height, thermal conductivity is low, thermal coefficient of expansion is low, ability is heated and vibratory impulse, density is low and porosity and permeability are very high.

Filtering substrate of the present invention is handled with one or more chemical addition agents alternatively.

In the another embodiment, the present invention relates to a kind of diesel engine particles trap, it comprises the filter of not using any catalyst described herein.

In another embodiment, the present invention relates to a kind of diesel engine particles trap, it comprises and CRT ^Diesel engine particles trap (NO _X, the HC absorber) combination filter described herein.

In another embodiment, the present invention relates to a kind of diesel engine particles trap, it comprises the filter described herein with the SCR combination.

In another embodiment, filtering substrate comprises many passages, as the back in greater detail.And, filtering substrate can be aspect one or more through modification, change and/or strengthen, as described herein and/or as known in the art.

The attribute of catalysis and filtering substrate

The present invention has one or more attributes that are better than conventional catalyst or filtering substrate, and preferably at least three, four, five, six, seven, eight, nine or ten kind of attribute.

Be fit to purposes

In some embodiment, the present invention relates to catalyst substrates or filtering substrate, it comprises nSiRF-C and catalyst, is applicable to catalytic converter.Described base material is applicable to many catalytic converters, filter and their application.

For example, catalyst substrates of the present invention and filtering substrate are applicable to any application that generally is used for the prior art base material.The purposes that is fit to includes but not limited to use base material of the present invention in any following gas extraction system: 1) movably road engine, equipment and the vehicles comprise automobile and light truck; Highway and street motorcycle, motor tricycle (for example motor tricycle, autorichshaws), motor tricycles motorcycle; Heavy-duty highway engine such as truck and bus; 2) movably non-road engine, equipment and the vehicles comprise compression ignition engine (agricultural, building, mining etc.); Small-sized spark ignition engine (hay mover, fallen leaves purging machine, chain saw etc.); Large-scale spark ignition engine (forklift, generator etc.); Marine diesel engine (commercial ship, amusement with diesel engine etc.); Spark ignition engine peculiar to vessel (ship, private ship etc.); The amusement vehicles (snowmobile, cross country motorcycle, all-terrain vehicle etc.); Locomotive; Aviation instrument (ROV, ground-support equipment etc.); With 3) stationary source, it comprises hundreds of sources, as power plant, refinery and manufacturing facility.

In another embodiment, catalyst substrates of the present invention is applicable to special car, if base material described herein (as catalytic converter a part of time) works and will make vehicle satisfy defined 1990,2007 and 2010 the arbitrary discharge standard of EPA.

In another embodiment, catalyst substrates efficient catalytic pollutant changes into the reaction of uncontamination thing.For example, change into the uncontamination thing with efficient catalysis pollutant greater than 50%.In another embodiment, change into the uncontamination thing with efficient catalysis pollutant greater than 60%.In another embodiment, described conversion ratio is selected from 70%, 80%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% and 99.9% again.In some embodiment, conversion ratio means the total conversion of non-particulate pollutant.In another embodiment, conversion ratio refers to the conversion ratio of specific non-fume, and for example NOx changes into N ₂, CO changes into CO ₂, or HCs change into CO ₂And H ₂O.In other embodiment, conversion ratio means the percentage of the particle of removing from waste gas.

In another embodiment, catalyst substrates of the present invention is applicable to special applications, if described catalyst substrates is passed through that some OEM stipulates and preferably tested as U.S.Federal TestProtocol 75 (U.S.FTP75).These tests are known in the art.(the EPA420-R-92-009 file referring to for example U.S.EPA announces can obtain at http://www.epa.gov/otaq/inventory/r92009.pdf, and its content all is incorporated herein for reference).In addition, EPA and/or state/municipal corporation may must be ratified these products and be used as back catalytic converter or DPT in improving application, comprises wherein contained base material.

Surface area

The useable surface area of base material is the key character of filtering substrate or catalyst substrates.One of the feature that is applicable to the base material of catalytic converter is to have high geometrical surface (GSA).High GSA allows maximum reaction probability.

Big front openings area (OFA) allow more substantial gas by and do not hinder it and flow and produce back pressure.Front openings area (OFA) is defined as the part (being the cross-sectional area of filter inlet passage) that can be used for gas flow in total cross-sectional area of base material.Usually represent with respect to total cross section of base material.

An attribute of base material of the present invention is its surface area height or GSA height.The surface area of base material is the key character of catalytic applications.Surface area is the surperficial total amount that toxic emission must be crossed when passing waste gas filter.The surface area increase is converted into the area that chemical reaction and catalysis and thermal process take place between the pollutant to be increased, and makes the catalytic converter process faster and more effective.Speed and efficient can cause taking place hardly to not stopping up, and obstruction may cause gas extraction system to be out of order.And the long-pending increase of the substrate surface of some embodiment comprises that also filter efficiency and/or ability improve.

Geometrical surface is the total surface area that can flood noble metal on it in one cubic inch.The base material that total surface area is high is preferred.But certain embodiments of the invention have the geometrical surface of the impregnated catalyst more much higher than traditional base material such as cordierite and SiC.

The general wall volume is the long-pending total amount of wall body that exists in one cubic inch of moulding base material.The general wall volume multiply by separately wall thickness with the surface area of each wall sues for peace then and calculates.The less base material of general wall volume is preferred.In some embodiment, the general wall volume ratio of base material of the present invention tradition substrate material such as cordierite and SiC are little.

In some embodiment, the general wall volume of catalyst substrates is about 0.5 to about 0.1, about 0.4 to about 0.2 or about 0.3in ³/ in ³(cubic inch/cubic inch).In a kind of preferred embodiment, the general wall volume of base material is about 0.25 to about 0.28, more preferably from about 0.27, more preferably from about 0.272in ³/ in ³

Because general wall volume of the present invention is less in some embodiment, so the amount that the present invention finishes required catalyst of catalytic action such as palladium than the cordierite of similar size is low.

Porosity and permeability

The hole attribute also influences the machinery and the hot attribute of base material.Can have balance between porosity and the mechanical strength: for some traditional base material, the base material that the aperture is less and porosity the is lower substrate intensity more higher than porosity is higher.In some material (Yuuki 2003), hot attribute-specific heat capacity and thermal conductivity all may be along with porosity increases and reduces.

The first wall streaming overall structure that the later stage 1980s introduces has the passage of diameter up to 35 μ m.For making filter efficiency the highest, passage is done forr a short time, and channel diameter is usually in the 10-15 mu m range in the filter of nineteen nineties use.In the exploitation new material, filter manufacturer's considers that mainly the catalyst system therefor system distinguishes its target hole attribute (Ogyu, K., et al., 2003. " Characterization of Thin Wall SiC-DPF ", SAE2003-01-0377; Yuuki, K., et al., 2003, " The Effect of SiC Properties onthe Performance of Catalyzed Diesel Particulate Filter (DPF), " SAE2003-01-0383).Application can followingly be classified:

Non-catalytic filter, as the filter that uses in the diesel fuel additives regenerative system: major requirement is a cigarette ash volume height.The porosity of some conventional filter is about 40-45%, has the hole between the 10-20 μ m.

Catalytic filter, as in the passive regeneration system those, thereby requiring that the bigger and aperture of porosity is bigger as far as possible can be with complicated day by day catalyst system (for the simple catalyst that does not almost have or do not have the wash coat material usually that uses with respect to nineteen nineties) coating.Base material is being used about 50g/dm ³After the catalyst of load/wash coat system coating acceptable low pressure loss should be arranged.The porosity of some prior art filter is in about 45-55% scope.Also may use extra heater.

Filter/NOx absorber device such as DPNR system or CRT (cyclic regeneration trap) have merged NOx storage/restoring system, need very high wash coat load, may be higher than 100g/dm ³The porosity of some prior art base material is about 60% (to have reported the base material of 65% porosity, mechanical strength becomes the major limitation (Ichikawa that improves porosity, S. etc., 2003, " Material Development of High Porous SiC for Catalyzed DieselParticulate Filters, " SAE 2003-01-0380).

Another attribute of some embodiment of catalysis of the present invention or filtering substrate is its porosity height.In some embodiment, the porosity of base material of the present invention is about 60%, 70%, 80% or 90%.In other embodiment, the porosity of base material is about 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% (representing with respect to the percentage of solid substrate with interstitial space).

In a kind of embodiment, the porosity of example embodiment of the present invention is about 97.26%.Compare mutually, cordierite is about 18-42%.In this embodiment, material of the present invention 2.74% material of only having an appointment hinders flowing of waste gas.This fine-structure mesh of material is caught particle effectively and very effectively it is burnouted.Owing to, a large amount of PM accumulations under the situation of recovery time, do not occur than PM length integration time in the in-depth filtration mode rather than only along conduit wall capture particle.The interaction that the porosity height is converted between pollutant and catalysis or the on-catalytic substrate surface is better more effective.Simultaneously, can laterally reach the air-flow that gathers along the release of expection gas flow direction.

Referring to Figure 22 a and 22b, example base material 2200,2205 of the present invention is shown.Base material 2200,2205 about 97% porous.Cordierite is compared with carborundum sample among Fig. 3 among Fig. 2 a substantially all identical with ratio and the 2b, and the hole of base material 2200,2205 is more and more not fine and close.Among Figure 22 b, be shown to scale particle PM-10 2210 and PM-2.5 2225.Compare with the cordierite sample 205 that Fig. 2 b exemplifies, particle PM-10 2210 and PM-2.5 2225 can permeate the fiber of base material 2205 easily.And, to compare with the carborundum 300 of Fig. 3, the density of carborundum is about 30-50 times of base material 2200,2205 density.

Certain embodiments of the invention mesopore rate is high more, and then surface area is big more and back pressure is low more.As a result, the present invention more effectively makes NOx reduction, hydrocarbon and CO oxidation and trap particulate matter.

Hole characteristic comprises that percentage by volume porosity, pore-size distribution, structure and interconnection determine the ability of described overall structure filtering particle.In addition, if gas molecule can diffuse in the porous substrate, then the probability of catalytic reaction significantly increases.The geometry in porosity feature and hole also influences integrally-built liquid flowing resistance and pressure drop.High desired some attribute of filter efficiency (for example porosity is low little with the aperture) is opposite with the low desired attribute of pressure drop.Low and the efficient of pressure drop is high all require between the hole connective good and do not have a closed pore dead end hole etc.Base material of the present invention provides filtration efficiency and low pressure drop in another embodiment.

Radiance and thermal conductivity

Another base materials employed in catalytic converter and particulate filter character is radiance.Radiance is the tendency of radiations heat energy; The relatively easy property of radiation or the speed that radiation is carried out are with regard to regard to the heat radiation on heated object surface.

Desirable base material is considered temperature, and this temperature (1) full out reaches high transformation efficiency; (2) be subjected to dangerous minimum (for example, because thermal shock or because the high temperature melting of base material/break) of pyrolytic damage; (3) use minimum auxiliary energy; (4) produce cheaply.The rising temperature needs additional-energy and expense height.In addition, a certain amount of energy conducts, derives or guide away by thermal conductivity.

Radiance is the ratio of reflection, and it is worth between 0 and 1, and 1 is total reflection.The different substrate materials that is used for catalytic converter and particulate filter has different emissivity values.The radiance height make catalyst substrates can will spread out of the heat of system minimize, thereby the air of heatable catalytic converter or particulate filter inside quickly.Radiance is the tolerance of the heat reflectivity of material, and high numerical value is expected.

In some embodiment, preferably have an appointment 0.8 to 1.0 radiance of base material of the present invention.In another embodiment, the radiance of base material of the present invention is about 0.82,0.84,0.86,0.88 and 0.9.The value of being more suitable for of base material radiance of the present invention comprises 0.81,0.83,0.85,0.87 and 0.89.In other embodiment, radiance is about 0.9,0.92,0.94,0.96 or 0.98.Heat reflectivity can be heated the gaseous material in the hole quickly, because base material itself keeps heat hardly.This causes lighting a fire faster and the base material outer surface heats up hardly.

The thermal conductivity of material is that the opposite face at sheet material is in the heat that is transmitted through the sheet material unit are under the situation of unit temperature gradient (for example unit thickness temperature difference 1 degree) in the unit interval.The unit of thermal conductivity is for watt/meter opening (W/m-K).In the preferred embodiment, base material of the present invention has lower thermal conductivity.For example, in a kind of embodiment, the thermal conductivity of base material of the present invention is lower than about 0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8 or 0.9.In another embodiment, the thermal conductivity of base material of the present invention is lower than about 0.01,0.02,0.03,0.04,0.05,0.06,0.07,0.08 or 0.09.In another embodiment, the thermal conductivity of base material of the present invention is about 0.1 to about 0.01, about 0.2 to about 0.02, about 0.3 to about 0.03, about 0.4 to about 0.04, about 0.5 to about 0.05, about 0.6 to about 0.06, about 0.7 to about 0.07, about 0.8 to about 0.08 or about 0.9 to about 0.09.In another embodiment, thermal conductivity of the present invention is about 0.0604W/m-K.

Compare mutually, the cordierite sample is about 1.3W/m-K to 1.8W/m-K.These results show: as an example of specific embodiments, if lose 1000 watts of heat energy from the cordierite material of given volume, then the material of the present invention from equal volume only loses 33 watts.Therefore, the thermal conductivity of material of the present invention is 30 times of cordierite.

In addition, in other embodiment, the preparation method of base material comprises that also preparation also comprises the catalyst substrates or the filtering substrate of radiopotentiator, and described method comprises to described base material, preferred nSiRF-C, more preferably AETB, OCTB or FRCI material apply radiopotentiator.Other preferred substrate comprises any concrete base material disclosed herein.In other embodiments, catalyst substrates also comprises radiopotentiator and is selected from palladium, platinum, rhodium, their derivative, and their catalyst of mixture.Other physics described herein and chemical modification can be used for these embodiments.Radiopotentiator is known in the art.

Hot attribute

The base material that thermal coefficient of expansion is low can tolerate fast variations in temperature and not have marked inflation or contraction.The thermal coefficient of expansion that is fit to also make base material thermal expansion rates can with neonychium around it and jar thermal expansion rates identical.

Also the preferred substrates material can tolerate the high-temperature scope, thereby when temperature rises to very high value, for example in the Ou Ran fuel combustion process, does not make the fusing of catalytic converter or particulate filter.In addition, if substrate material can tolerate high temperature, then catalytic converter or filter can place the position of more close engine.

Relevant character comprises that caloic and thermal capacitance are low.The heat energy of material waste in catalyst substrates heats up that caloic and thermal capacitance are low is less.If the catalyst substrates Fast Heating, then the heat energy that brings by waste gas is used to trigger the catalytic component igniting.

Thermal conductivity is material conducts heat because of molecular motion a ability.More specifically, thermal conductivity also is that the sheet material opposite face temperature difference is 1 when spending, the tolerance of the heat of the unit are by unit thickness sheet material in the unit interval.Material heat conduction is many more, overcomes loss and meet the requirements of temperature institute energy requirement many more.Preferred material reflecting heat but not heat conduction.Heat conductivity value is low to be preferred, thereby more thermal energy is used for hole, does not lose because of being absorbed by base material.The chemical property decision thermal conductivity level of different material.In addition, the thermal conductivity of filter medium is the major influence factors of exhaust emission filter efficient, because temperature loss influences reactivity unfriendly.Thermal conductivity is low to be preferred, because the heat energy that produces is reflected by particle more, and stays in the hole.In other words, thermal conductivity is low more, and heat loss is low more.Heat loss is lower to be converted into that to reach temperature range that catalyzed conversion requires institute energy requirement lower and efficiency is higher.

Specific heat is the temperature rising 1 degree centigrade of institute's calorific requirement (calorie) that makes 1 gram material.The high base material of specific heat is heat (for example from waste gas or auxiliary source) the reflected back hole of surrounding environment, needs this heat at interstitial space internal combustion or catalytic reduction and oxidizing process.For example, arctic for example under extreme conditions, the filter of the low specific heat of heating and the time that the filter cooling of heat is needed are longer, and the possibility that external heat is destroyed increases.Specific heat is low to be preferred, because faster and reach operating temperature with still less energy.

In some embodiment, base material of the present invention has many preferred hot attributes.Preferred material causes the heating that adds the ratio of specific heat base material of air in the hole preferentially to be carried out.The fusing point height of preferred base material of the present invention, in some embodiment, fusing point is than traditional base material height.The fusing point height is preferred, and partly cause is that catalyst substrates or filtering substrate are exposed to extreme temperature.

In a kind of preferred embodiment, base material of the present invention preferably has high-melting-point.In a kind of embodiment, fusing point is greater than about 1500 .In another embodiment, fusing point is greater than about 2000 .In another embodiment, fusing point is greater than about 2500 .In another embodiment, the fusing point of base material is that about 2000  are to about 4000  again.In another embodiment, the fusing point of base material is that about 3000  are to about 4000  again.Other melting range that is fit to comprises about 3000 to about 3100, about 3100 to about 3200, about 3200 to about 3300, about 3300 to about 3400, about 3400 to about 3500, about 3500 to about 3600, about 3600 to about 3700, about 3700 to about 3800, about 3800 to about 3900, about 3900 to about 4000.In another preferred embodiment, the fusing point of base material is about 3632 .

In a kind of embodiment of the present invention, the fusing point of base material is about 3632 .For example, if vehicle is in below the solidification point, the smoke evacuation of one 1500  can not cause base material to break or rupture.Similarly, some embodiment of base material can be not overheated and be broken.Some sample fusing point of cordierite is about 1400 ℃.

The specific heat of the present invention's one example embodiment is about 640J/kg-K (joule/kilogram-Kai).The cordierite sample is about 750J/kg-K.Even cordierite has bigger specific heat, the quality that cordierite filters will heat is also bigger.The result is that to reach the required heat energy of operating temperature more, makes the efficient of cordierite lower.

Repeatedly the serviceability temperature limit is that material can stand repeatedly and the maximum temperature of essentially no degeneration.Base material can continue to work and not have the temperature of fine fisssure or spallation high more, and the possibility that base material ruptures along with the time or breaks is more little.This means that again base material is more durable in wideer temperature range.Preferred higher repeatedly serviceability temperature limit.The repeatedly serviceability temperature limit that is suitable for some embodiment of catalysis of the present invention or filtering substrate is selected from about 2000 ℃, 2100 ℃, 2200 ℃, 2300 ℃, 2400 ℃, 2500 ℃, 2600 ℃, 2700 ℃, 2800 ℃, 2900 ℃, 3000 ℃ and 3100 ℃.

The repeatedly serviceability temperature of the present invention's one example embodiment is limited to 2980 ℃.The cordierite sample is about 1400 ℃.The embodiment of the present invention can tolerate the many temperature of twice of cordierite before breaking.This can work described material in wider exhaust environment.

Thermal coefficient of expansion be given intensification (being generally 0 to 1 ℃) down length (linear coefficient), area (surface) or the volume of object increment respectively with the ratio of raw footage, area or volume.The ratio of these three coefficients is about 1: 2: 3.Do not have when clearly representing, mean the coefficient of cubical expansion usually.Base material expands fewly more during heating, and the possibility that filter assemblies leaks, breaks or damages is more little.Even preferred thermal expansion is low to guarantee that base material keeps its size when heating or cool off.

The thermal coefficient of expansion of example embodiment of the present invention is about 2.65 * 10 ^-6W/m-K (watt/Mi-Kai).The cordierite sample is about 2.5 * 10 ^-6W/m-K to 3.0 * 10 ^-6W/mK.Material coefficient of thermal expansion of the present invention is less than 10 times of cordierite.

The thermal coefficient of expansion of base material is preferably compatible with the thermal coefficient of expansion of any wash coat.

In a kind of embodiment, catalysis of the present invention or filtering substrate are compared with some prior art base material such as cordierite, and the repellence of damaging due to thermal stress or the mechanical stress is improved; Danger by cigarette ash and/or dust obstruction reduces; More tolerate the accumulation of additive dust when using with fuel additive regeneration; And the efficient that reduces amounts of particles is good.

Density

During base material that consideration will be used, preferably use low density base material in catalytic converter or diesel particulate filter.Low density material makes base material weight saving, thereby the gross weight of vehicle is alleviated.In addition, low-density can be replenished porosity and permeability height.

The higher weight that is converted into of density is higher.Weight be in the running any engine intrinsic key factor.Parts are heavy more, and it is high more to make it mobile institute energy requirement.For making these filters hold the grain amount that increases that engine produces, filter size must increase, and this makes car weight and manufacturing and operating cost increase again.Therefore, more low-density material is expected.Certainly, density can not be too low so that structural intergrity is not enough.

Another attribute of base material of the present invention is its density.The density of described base material is lower than the density of some conventional filter that is used to filter and be used as catalyst substrates and base material.Density is the quality of material and the ratio of its volume.Density more then reaches operating temperature needs more energy.In other words, the not finer and close material require more energy of heating dense material.For prescribed volume, it is bigger that density more directly changes into weight.Weight is unfavorable to the mileage and the performance of vehicle, must work more hardy because will move heavier equipment engine.The density increase also is converted into and reaches the more heats of temperature needs that are fit to take place catalytic activity or " igniting ".The density that is used as some materials of base material or filter at present is higher than optimum value.For example the cordierite sample is about 2.0g/cm ³To 2.1g/cm ³Therefore, need lower base material of density and filter.The density of base material of the present invention is lower than the density of cordierite.

In a kind of embodiment, catalyst substrates of the present invention preferably has low-density.The density of base material of the present invention can be about 2 to about 50 pounds of/cubic feet (lb/ft ³) scope in.In the preferred embodiment, the density of base material is at about 5 to about 30 pounds/cubic feet, more preferably from about in 8 to 16 pounds/cubic feet the scope.Other preferred embodiment comprises that density is about 8,9,10,11,12,13,14,15 or 16lb/ft ³Catalyst substrates.Preferred low-density of still giving structural intergrity.

In a kind of embodiment, the density of base material of the present invention is about 8lbs/ft ³And 22lbs/ft ³, preferably about 8lbs/ft ³And 22lbs/ft ³In another embodiment, described base material comprises AETB-8 or AETB-16, and density is respectively about 8lbs/ft ³With about 16lbs/ft ³Other density that is fit to comprises and is selected from about 9,10,11,12,13,14,15 and 16lbs/ft ³Density.

In another embodiment, the density of described base material is about 0.10g/cm ³To about 0.25g/cm ³(gram/cubic centimetre).

Structural intergrity

The structural intergrity of substrate material is the key character that needs consideration.Structural intergrity means material and stands to vibrate the ability of promptly shaking and toasting with mechanical stress.For example, substrate intensity is extremely important for standing to pack load and being used for engine efflux subsequently, is subjected to the influence that various stress comprise engine luggine, road vibrations and thermograde relatively.Firm catalyst system and particulate filter need the high strength base material.The intensity of substrate material can be controlled by intracrystalline and intergranular bond type, porosity, pore-size distribution and defective number.In addition, can be by strengthening base material at the inboard of appearance coating chemistry/material coating.The intensity of base material loose structure may also depend on the geometry and the wall thickness of its size, cross section symmetry and hole attribute thereof such as hole density, passage.Substrate intensity must surpass the stress that material is subjected in packing and the operation process.If stress surpasses intensity, base material will break.

The structural intergrity of material can be by the stretch modulus tolerance of material.Stretch modulus is the resistance to fracture of material.Particularly, be to stand great longitudinal stress not tearing under the fragmented situation material.Stretch modulus represents with respect to the unit cross-sectional area usually, is the kilogram number that produces the needed pounds per square inch (p.p.s.i) of fracture or every square centimeter.Stretch modulus is relevant with the power whether base material can tolerate fierce waste air flow pressure generation.

In addition, but thereby base material also should have good screening characteristics can apply wash coat and/or catalyst coatings on base material.Similarly, described base material should have the compatibility with wash coat, thereby makes catalyst can be fixed on the base material its position of catalyst non-migration during the normal wear of system well.But screening characteristics and well also improve the long-term efficacy of catalyst system with the compatibility of wash coat.But screening characteristics and well also prolong life of catalyst with the compatibility of wash coat.

Another attribute of base material of the present invention is its structural intergrity.The structural intergrity of material can be by the stretch modulus tolerance of material.Stretch modulus is the resistance to fracture of material.Particularly, be to stand great longitudinal stress not tearing under the fragmented situation material.Stretch modulus represents with respect to the unit cross-sectional area usually, is the kilogram number that produces the needed pounds per square inch (p.p.s.i) of fracture or every square centimeter.Stretch modulus is relevant with the power whether base material can tolerate fierce waste air flow pressure generation.

Catalyst substrates of the present invention preferably has higher stretch modulus.For example, in a kind of embodiment, the axial strength of base material of the present invention is about 2.21MPa.Certainly, higher axial strength also is fit to.Other value that is fit to comprises 1,2,3,4,5,6,7,8,9 and 10MPa.

In addition, the structural intergrity of catalyst substrates of the present invention makes it to tolerate the condition that it runs between the operating period in catalytic converter in commercial car.

In another embodiment, base material of the present invention for example nSiRF-C preferably has high structural intergrity and low-density.

Pollutant reduces

Base material is playing a significant role aspect the catalytic activity that strengthens coating catalyst material thereon.Base material also is used for trap particulate matter, and it is burnt becomes escaping gas then.

Another advantage of base material of the present invention is that its ability that reduces amount of pollutant in the waste gas improves.Catalysis of the present invention and filter capacity strengthen than some conventional art.

In some embodiment, base material of the present invention can make in the waste gas CO discharging be reduced by at least about 50%.In a kind of embodiment, base material of the present invention can make in the waste gas CO discharging be reduced by at least about 60%, 70%, 80% or 90%.In another embodiment, base material can make the CO discharging be reduced by at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9% or 100%.

In some embodiment, base material of the present invention can make in the waste gas NOx discharging be reduced by at least about 50%.In a kind of embodiment, base material of the present invention can make in the waste gas NOx discharging be reduced by at least about 60%, 70%, 80% or 90%.In another embodiment, base material can make the NOx discharging be reduced by at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9% or 100%.

In some embodiment, base material of the present invention can make in the waste gas HC discharging be reduced by at least about 50%.In a kind of embodiment, base material of the present invention can make in the waste gas HC discharging be reduced by at least about 60%, 70%, 80% or 90%.In another embodiment, base material can make the HC discharging be reduced by at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9% or 100%.

In other embodiments, base material of the present invention can make in the waste gas VOC discharging be reduced by at least about 50%.In a kind of embodiment, base material of the present invention can make in the waste gas VOC discharging be reduced by at least about 60%, 70%, 80% or 90%.In another embodiment, base material can make the VOC discharging be reduced by at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9% or 100%.

In other embodiments, base material of the present invention can make in the waste gas PM-10 discharging be reduced by at least about 50%.In a kind of embodiment, base material of the present invention can make in the waste gas PM-10 discharging be reduced by at least about 60%, 70%, 80% or 90%.In another embodiment, base material can make the PM-10 discharging be reduced by at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9% or 100%.

In other embodiments, base material of the present invention can make in the waste gas PM-2.5 discharging be reduced by at least about 50%.In a kind of embodiment, base material of the present invention can make in the waste gas PM-2.5 discharging be reduced by at least about 60%, 70%, 80% or 90%.In another embodiment, described base material can make the PM-2.5 discharging be reduced by at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9% or 100%.

Weight saving

Automaker's target is to reduce the gross weight of vehicle to improve its fuel economy and engine efficiency.Heavy base material has increased unnecessary weight to vehicle.In addition, effective inadequately if base material reduces pollution, then may need to place more than a base material to reach the target stains level.This increases gross combination weight greatly.

In addition, present catalytic converter need use attachment device, and these devices are very heavy usually.In these devices some for example hot baffle and special bed course are used to deal with the temperature of catalytic converter.Other for example lambda sensor is that to meet some government regulation needed.

In the certain embodiments of the invention, the weight ratio conventional catalyst of catalyst substrates or filtering substrate or the weight saving of filtering substrate.Partly cause is that the density of base material of the present invention is lower than the density of some traditional base material.Perhaps, thus weight gentlier may be because the filtration of certain embodiments of the invention and catalysis improve the requirement that causes catalysis or filtering substrate than conventional art reduces.The weight of catalysis or filtering substrate gentlier has many benefits.For example, the weight of base material gentlier can be converted into the fuel efficiency improvement of vehicle.And weight gently also is converted into easier manipulation and the safer hand-held engine device of possibility.

In a kind of preferred embodiment, the outer surface of base material is not heated to the degree identical with the conventional catalytic converter base material in the use.In some embodiment, hot baffle and/or adiabatic needing are reduced.

Acoustic properties

Acoustic attenuation may be defined as thickness, thinness, thin degree and reduces; Density reduces; Power or intensity reduce; Or acoustic energy (sound) decay.In one embodiment of this invention, acoustic attenuation is the ability that base material weakens or weaken acoustic energy in the engine exhaust.Base material of the present invention can replace or the muffler assembly (as disclosed herein) of additional engine, thereby reduces exhaust noise and gas extraction system cost.Acoustic attenuation is higher to be preferred.

In another embodiment, porosity, density and the size that can change base material with " adjustment " at the acoustic attenuation that will use.

In another embodiment, the acoustic attenuation of base material can combine with the technology based on the standard metal silencer with the sound that weakens and/or " adjustment " gas extraction system exists.

Pattern of flow

Through-flow type

On the one hand, the structure base material is to be used for through-flow type.Through-flow be configured as known in the art.In a kind of embodiment, passage (or hole) is arranged parallel to each other basically in the whole length of base material.Air-flow at one end enters base material, advances along passage and leaves at the other end by the whole length of base material.

Many through-flow configurations are suitable for and are suitable for catalyst substrates of the present invention.Through-flow configuration known in the art can be applicable to catalyst substrates of the present invention.

In a kind of embodiment, through-flow configuration comprises many substantially parallel passages that run through base material length fully.

In another embodiment, conduit wall is not parallel to the side or the surface of base material.

The wall flow pattern

Another embodiment of the present invention is catalyst substrates of the present invention or the filtering substrate with wall stream configuration structure.Determine in surprise and can will comprise the catalyst substrates structure wall-forming stream configuration of nSiRF-C of the present invention.

Another aspect of the present invention, base material have wall stream configuration.For example base material is used for wall-flow type catalytic converter or wall-flow particulate filter.Wall stream configuration can adopt any one in many physical arrangement.Base material with wall stream configuration can have one or more attributes described herein.And the base material with wall stream configuration can also comprise following one or more: catalyst, wash coat, storage oxygen oxide and radiopotentiator.In addition, the base material that constitutes by wall stream configuration can further modification as described herein, enhancing or change.

In a kind of embodiment, channel wall thickness is following arbitrary value.Preferred channel wall thickness in about 2 mils to about 6 mil scopes.In other embodiment, channel wall thickness in about 10 mils to about 17 mil scopes.Other fit value comprises 2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19 and 20 mils.

In other embodiment of wall-flow type base material, the hole density of base material is about 2 mils for about 6 mils or hole density for about 900cpsi channel wall thickness for about 400cpsi (hole count per square inch) wall thickness.Other embodiment comprises that hole density is about 50,100,150,200,250,300 or those of 350cpsi.

The wall flow type ceramic overall structure of being derived by the throughflow type porous carrier that is used for catalytic converter becomes the diesel filter base material of common type.The characteristic that they are different from the design of other diesel filter is the high and filter efficiency height of surface area of unit volume.Whole diesel filter is made of many parallel passage aisles, and described passage has square sectional usually, axially runs through described parts.Obtain the diesel filter overall structure by the throughflow type overall structure by blocking channel.Alternately stopping up adjacency channel at each end forces diesel engine smog to pass through the porous substrate wall of mechanical filter effect.For reflecting this flow pattern, described base material is called the wall-flow type overall structure.The most frequently used in cylindrical is the wall-flow type overall structure, but the parts of oval cross section also can be used for the application of limited space.

The flow honeycomb filter wall has segmentation cloth hole, must distribute by the control pore in the manufacture process.The filtration mechanism of overall structure wall-flow filter is filter cake and in-depth filtration combination.In-depth filtration is a dominant mechanism on the clean filter, because particle deposition is in the inboard, hole.Along with cigarette ash load increases, on the inlet channel wall, form stratum granulosum, and cake filtration becomes dominant mechanism.The filter efficiency of the monolithic filter that some is traditional is about 70% of a total particulate (TPM).Can be observed higher efficient for solid PM cut such as simple substance carbon and metal ashes.

According to certain embodiments of the present invention, preferably have porous materials, thereby more gas can pass through the hole easily, interact with the catalyst that is deposited on the fibrous composite in-core.In addition, have porous wall in some embodiment and can make the degree of in-depth filtration higher, this also is the attribute of expectation.

The base material of the present invention of wall stream configuration contacts much direct with waste gas.The hole characteristic of material (connectedness in aperture, porosity, hole, perforate and closed pore etc.) influences the physics interaction between gas and the filtering material and influences attributes such as filter efficiency and pressure drop.In addition, the durability of base material depends on the repellence of material to the exhaust gas constituents chemical erosion.Especially, the corrosion of the material require ashes of anti-the metal, the metal ashes can be the parts of diesel engine particles.Also need sulfuric acid corrosion resistant, especially filter is when the fuel of higher sulfur content uses.In addition, owing to may discharge a large amount of heat in the filter regeneration process, filter material also need show excellent hot attribute aspect high temperature resistant and the high-temperature gradient.The temperature tolerance deficiency may cause material fusing, and the resistance to sudden heating deficiency causes and breaks.Other potential problems comprise fine fisssure and spallation.In the particular embodiment, one or more during filtering substrate of the present invention and catalyst substrates solve these problems.

The important parameter that need consider during the integrally-built definite geometry of design wall-flow type comprises: hole density, repeat distance (pressure drop on the whole wall-flow filter is evenly distributed), wall thickness, front openings area, concrete filter area and mechanical integrity factor.

In the specific embodiments of the present invention, the wall-flow type configuration seals a hemichannel.In another configuration, base material of the present invention has the wall-flow type configuration, and wherein the closure wall of passage is positioned at the initiating terminal or the end of passage.In another configuration, closure wall is positioned in the middle of the passage, perhaps any position between passage initiating terminal and end alternatively.

In addition, the wall-flow type configuration can comprise any percentile passage, for example 10%, 25%, 50%, 75%, 90%, 95% etc.

Passage and access portal

In a kind of embodiment, catalysis or filtering substrate do not comprise the many passages that run through base material length.In some embodiment, for the base material that for example works in the catalytic converter in its desired use, the catalysis or the filtering substrate of given its porosity and permeability do not need the passage that is positioned at base material.By emission being placed in the path of catalyst substrates, only reduce any possible back pressure by porosity and permeability.If adopt the film configuration that does not have passage, then advantageous applications is to reduce the possibility that matrix structure damages in the environment of low flow velocity.The film configuration is preferred in " low flow velocity " environment such as the fireplace or can be in the power plant.Here be constant (power plant) under low and some situation of flow velocity.Certainly, should understand this configuration and also be suitable for other application, comprise the vehicles and stationary engine.

In another embodiment, catalysis of the present invention or filtering substrate have a plurality of passages that vertically run through at least a portion base material in one embodiment.A plurality of passages allow fluid media (medium)s, and for example gas or liquid pass base material and flow.A plurality of passages extend to the rear surface from front surface.Other passage can extend to front surface from the rear surface.

Described passage can run through the whole length of base material.In this embodiment, passage will have the first passage opening that is positioned at the base material front surface and be positioned at the second channel opening of rear surface.Perhaps, passage runs through the part of base material.In some embodiment, passage runs through about 99%, 97%, 95%, 90%, 85%, 80%, 70%, 60% or 50% of base material length.

The access opening of base material or access portal can be made many shapes.For example, access portal can be circle, triangle, square, hexagon etc.In the preferred embodiment, access portal is triangle, square or hexagon.

In a kind of embodiment, form access portal and make that the thickness of host material is consistent basically between the interior adjacency channel of whole base material.Wall thickness change can be about 1% to about 50% in some embodiment.

In another embodiment, arrangement channel makes the wall of adjacency channel be parallel to each other.For example, thus the wall that can form triangle, square or hexagonal channel adjacency channel is parallel to each other.

The diameter of base material internal channel of the present invention or cross-sectional distance can change.In some embodiment, the diameter of passage or cross-sectional distance are that about 5cm is to about 100nm.In some embodiment, channel diameter is about 100nm.Other fit value comprises distance or the diameter that is selected from about 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19 and 20 mils.

Passage can change along the size of its length.For example, passage can be about 0.04 inch in its opening part cross-sectional distance, and size reduces and gradually at end wall or the point of channel end near passage or opening then.In a kind of embodiment, the passage front surface is the square openings of about 10 mils of the length of side.Passage runs through base material length and second opening is arranged in the rear surface.The access portal of rear surface is the square of about 4 mils of the length of side.Passage diminishes from the front surface to the rear surface gradually along its length.Certainly can consider other similar configuration.

The size of access portal also can change.For example, in some embodiment, diameter (or cross-sectional distance) is about 1 to about 100 mils of mil.The suitable scope of other of access portal size including but not limited to about 1 to about 500 mils, about 1 to about 100 mils, about 1 to about 10 mils.Other suitable size comprises distance or the diameter that is selected from about 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19 and 20 mils.Base material of the present invention also can have the passage of different size.Some passages that are base material embodiment have a plurality of first passages of first diameter or cross-sectional distance and a plurality of second channels of second diameter or cross-sectional distance.As an example, in a kind of embodiment, base material of the present invention comprises one or more passages of about 5 mils of cross-sectional distance, also comprises one or more passages of about 7 mils of cross-sectional distance.Other modification that should understand these embodiments also within the scope of the invention.

In other embodiment, channel diameter or cross-sectional distance can be about 5cm, 4cm, 3cm, 2cm or 1cm.Have the base material than the passage of major diameter or cross-sectional distance to be preferred for bigger gas extraction system, these gas extraction system have the blast pipe of one foot of diameter or many feet.

The thickness of conduit wall also can change.For example, conduit wall can have the thickness less than 1 mil.Other fit value of passage wall thickness comprises 1,2,3,4,5,6,7,8,9 and 10 mils.

Passage can be measured with number of active lanes per square inch.In some embodiment, base material of the present invention has an appointment 50 per square inch to about 100,000 passages.Other fit value comprises 100,200,300,400,500,600,700,800,900 and 1000.Other embodiment comprises catalysis or the filtering substrate that 2000 passages are arranged per square inch.

In a kind of embodiment, base material of the present invention comprises the wall thickness of 600cpsi and 6 mils.With the hole density of base material sample of the present invention and two sample contrasts of cordierite.The first and second cordierite samples are respectively 100cpsi and wall thickness 17 mils, 200cpsi and wall thickness 12 mils.By contrast, base material of the present invention is 600cpsi and 6 mil wall thickness in this embodiment.

In a kind of example embodiment, across whole filter, base material is drilled with the passage of 0.04 inch diameter with 0.06 inch interval.These passages are littler than traditional cordierite wall circulation road.The result is that the surface area ratio cordierite increases a lot, even do not consider the interior surface area that exists of a large amount of holes of host material.Described passage is preferably " blind " passage.Toxic emission is forced to pass conduit wall, but not from passage flow to flow out and not with catalyst reaction.

Another embodiment relates to catalysis or the filtering substrate that comprises a plurality of pyramid shaped channels.The pyramid of passage makes it can be used for many host materials, comprises that base material of the present invention such as nSiRF-C also do not comprise other base material.Pyramid shaped channels can be constructed like this and be made each passage that two access portal all be arranged, and an opening that is positioned at the base material front surface and the through-flow configuration that is positioned at an opening of base material rear surface are for example arranged.Perhaps, pyramid shaped channels can be constructed like this and be made each passage have only an opening, for example wall stream configuration.In this embodiment, the opening of some passage is positioned at front surface, and the opening of other passage is positioned at the rear surface.Preferred passage is arranged the position that makes about access portal like this, and the configuration of adjacency channel is opposite.And in some embodiment of pyramid wall stream configuration, passage ends at the not boring part of base material.The not boring part of base material can be flat or sharp.If not boring part is flat, then the longitudinal cross-section of passage appears as trapezoidal.If not boring part is sharp, then the longitudinal cross-section of passage appears as triangle.

Shape and form

Catalysis and filtering substrate comprise many suitable and unknown so far configurations.Base material is three-dimensional, and front surface (or area or front) and rear surface (or area or front) of linking to each other with one or more side surfaces by substrate body are generally arranged.Front surface and rear surface can be many shapes described herein.Front surface means the surface of passing through when liquid enters base material.The rear surface means the surface of passing through when liquid leaves base material.The surface is normally flat, but can be uneven in some embodiment.

In some embodiment, described base material is columniform.The cylinder that is made of base material is used for for example catalytic waste gas NO reduction.

Many suitable length and width or diameter all are fit to base material of the present invention.The length that is fit to comprises 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19 and 20 inch.Certainly, in diesel applications and being used for fixing in the engine, may preferred longer length as base material used in pharmacy and chemical plant, manufactory and the power plant etc.On the other hand, the shape of base material can be according to the shape description of its front surface.Base material of the present invention can prepare like this makes front surface have one of several physical configurations.The shape of front surface can be many shapes, includes but not limited to circle, triangle, square, ellipse, trapezoidal and rectangle etc.Three-dimensional, described base material form can be cylinder or flat basically disk.Be purchased base material and be generally one of these two kinds designs.Base material can have right angle or fillet.For the shape of base material front surface, fillet is preferred.Therefore, in a kind of embodiment, base material shape of the present invention is the square that fillet is arranged.In another embodiment, base material front shape is the rectangle that fillet is arranged.In another embodiment, base material front shape is trapezoidal that fillet is arranged.

The typical sizes of catalyst substrates of the present invention includes but not limited to have circular cross section and diameter about 3.66, about 4.00, about 4.16, about 4.66, about 5.20, about 5.60 or about 6.00 inches base material.In other embodiment, catalyst substrates is the ovallized column shape, about 3.15 * about 4.75 inches of cross sectional dimensions (minor axis and major axis are respectively), about 3.54 * about 5.16 inches or about 4.00 * about 6.00 inches.

In another embodiment, catalyst substrates has the shape and size that are applicable to the front end catalytic converter.Usually, traditional catalytic converter is little on the front end catalytic converter size ratio engine gas extraction system.The suitable size and dimension of determining the front end catalytic converter is in those of ordinary skills' limit of power.The size and dimension of front end catalytic converter is based on the concrete front end and the engine construction that use with the front end catalytic converter.For example, the surface area of the about 4.5 inches circular base material of traditional cordierite of diameter is about 28.27 square inches.For example on Ford 4.6V-8, two pre-catalytic converters with approximate this size base material are arranged.These two traditional pre-catalytic converters can replace with the front end catalytic converter of eight nSiRF-C base materials, and described nSiRF-C comprises about 1.13 inches diameter.

Perhaps, come the oxidation of carbon monoxide and unburned hydrocarbon in the catalytic waste gas with cylinder.Cylindrical length can greater than, equal or less than cylindrical diameter.

According to concrete application examples such as stationary engine, road vehicle, off-road vehicle etc., can adopt the difformity and the configuration of filtering substrate and catalyst substrates.

In another embodiment, make the catalyst substrates moulding be purchased the base material of the commerce use of catalytic converter with replacement.In this embodiment, the shape and size of base material of the present invention are basic identical with the base material of the catalytic converter that gets that uses different substrate materials.For example, the many catalytic converters that use at present comprise the base material of being made by cordierite.The shape and size of the cordierite of catalytic converter are known or can determine by analyzing.Then by processing or as hereinafter described molding prepare base material of the present invention, make the shape and size of the shape and size of base material of the present invention and known cordierite substrates basic identical.

The film configuration

Perhaps, described base material has the film configuration.In this configuration, the length of base material is basically less than the width or the diameter of base material.In some conventional catalytic converter and the particulate filter, waste gas accumulates corresponding to back pressure than long by the length of travel of base material.In the thin base material of certain embodiments of the invention, back pressure is minimized, waste gas is more easily by filter system, and filter capacity improves.This of back pressure reduces to cause engine running more effective, means that the mileage oil consumption is better and more powerful.

In the one embodiment of this invention, 2 inches of substrate diameter, thick 1/16 inch, surface area is 4 inches of diameters, long 6 inches 400 times of traditional cordierite filters.Because the size of base material own reduces, a jar size also can reduce, and causes in the exhaust line only little projection.Perhaps, base material can be packed in the exhaust manifold.

In another embodiment, base material is a form of film.In the case, the film that comprises substrate material described herein has above-mentioned many shapes, and wherein the length of base material is basically less than width or diameter.Size can be described as for example width and length or diameter and length ratio.The diameter that is fit to includes but not limited to about 20: 1,19: 1,18: 1,17: 1,16: 1,15: 1,14: 1,13: 1,12: 1,11: 1,10: 1,9: 1,8: 1,7: 1,6: 1 and 5: 1 with the ratio of width.

And the base material with film configuration can be stacked with one or more independent base material embodiments.Have the film configuration, many catalysis or filtering substrates with film configuration can be stacked.For example, about 1 inch of a plurality of (for example 5) diameter, the catalysis of cylinder (or disk) shape or the filtering substrate that are about 0.2 inch can be stacked to form for example about 1 inch base material heap of certain-length.

Under the situation of film configuration, in a kind of embodiment, catalyst substrates does not comprise many passages that run through base material.Because gas must be advanced the distance of passing short and also partly since porosity height of the present invention and pressure drop is low can form to comprise a plurality of base materials heaps with catalyst substrates of film configuration.

And the stacked film configuration comprises that also wherein single base material is not orthogonal to the stacked film configuration of catalytic converter or particulate filter bottom surface.In this embodiment, base material can be processed like this or molding make angle between substrate side (side surface) and front (front surface or the rear surface) be about 90 ° less than or greater than 90 °, for example 80 °, 70 ° etc.

Add catalyst before the sintering

In another embodiment, catalyst substrates described herein also comprises catalyst, and wherein catalyst joined in the host material before sintering process.In the case, catalyst generally added in the slurry before forming green compact.In other embodiment, catalyst adds in the interior fiber of blender.Perhaps, if catalyst is liquid, in some embodiment catalyst is added in the slurry.Can form base material by the slurry that comprises one or more catalyst.In a kind of embodiment, catalyst adheres on the fiber of base material when sintering.In another embodiment, catalyst is positioned at the hole of conduit wall, and mainly attached to the conduit wall surface opposite.

The base material subregion

In another embodiment, prepare catalyst substrates described herein and make the not same district in the base material that different attribute be arranged.In other words, one or more physical characteristics of catalyst substrates or attribute are inconsistent or inequality in whole base material.For example, in some embodiment, there are different density, different catalyst, different catalyst mixture, different channel configurations, different porosity, different permeability and/or different hot attributes in the not same district of base material or zone.As an example, in a kind of embodiment, catalyst substrates of the present invention comprises the nSiRF-C composite and first and second catalyst, wherein said first catalyst coated in first district of described base material and described second catalyst coated in second district of described base material.In another embodiment, the structural intergrity degree difference of base material in the substrate body.For example, as described herein, can apply the density coating to improve its surperficial hardness at substrate surface, this will reduce possible infringement.

Wash coat

Another aspect of the present invention relates to catalysis described herein or the filtering substrate that also comprises wash coat.In other embodiment, catalyst substrates also comprises catalytic washcoat composition, and for example except that the wash coat material, wash coat also comprises catalyst.Perhaps, in another embodiment, the wash coat material has catalytic activity.

The wash coat that is fit to comprises silica, titanium dioxide, not oxide impregnation zirconium, the zirconia with the rare-earth oxide dipping, ceria, the rare-earth oxide-zirconia that forms together and their combination.Other wash coat that is fit to is disclosed in US6,682,706; 6,667,012; 4,529,718; 4,722,920; 5,795,456; With 5,856, in 263, these are open all be incorporated herein for reference.

In general, can apply wash coat by aqueous slurries in some embodiment.Alumina powder and/or other wash coat oxide are ground to desired particle size.The size distribution of wash coat powder influence final wash coat mechanical strength and with the adhesive force of base material and coating wash coat technical process in the rheological characteristic of slurry.In some embodiment with air-spray or ball mill grinding aluminium oxide (a kind of stone material).

In the next step, in being arranged, the jar of high-shear mixer make dispersion of materials in acidifying water.The solids content of slurry is generally 30-50%.Prolong after the mixing, aluminum oxide suspension becomes stable colloidal state system.

The amount that is deposited on the wash coat on the base material depends on the rheological characteristic of slurry (viscosity) and can control by it.The aluminium oxide slurry is the non-newtonian fluid that viscosity changes with the amount (shear rate) of delivery system mechanical energy in time under some situation.Under any stable shear rate, the viscosity of slurry is the function of its pH.In some embodiment, can be by regulating pH control viscosity.But because the non-newtonian feature of alumina system, accurately control viscosity the chances are maximum challenge in the coating wash coat technology.

Washcoat coating slurry can be applied on the base material with any known method and program, comprises dipping or is cast on the parts and/or with special coating machine.From passage, remove excessive slurry with compressed air.Thereby can wash coat be bonded on the integrally-built wall base material drying and calcining then.

In some embodiment, can apply one, two or more multi-layered wash coat.Every layer can be carried out drying and calcining before one deck under handling.Apply the multilayer wash coat several reasons is arranged: (1) Catalyst Design may need the chemical formulation difference of each layer, (2) coating/process equipment restriction, for example can not handle very sticking slurry, the thick wash coat of once-through operation coating needs very sticking slurry.

The typical thickness of wash coat is 20-40 μ m, but the value beyond this scope also can be used for the present invention.These numerical value are corresponding to for example wash coat load about 200g/L on about 100g/L to 400cpsi base material on the 200cpsi base material.The specific area of catalyst wash coat material is 100 and 200m in some embodiment ²Between/the g.Certainly, other value also is applicable to the present invention.

Noble metal and other catalyst may react to each other, react with the reaction of wash coat composition or with carrier material in complicated catalyst system, produce the compound of undesired catalytically inactive.If this type of reaction takes place in given catalyst system and catalyzing, then this is difficult to prevent in traditional washcoat technology.Because catalytic metal is immersed on the final wash coat, can not avoid reacting the contact between the composition.

Developed and isolated the washcoat technology and be fixed on the special base metal oxide of wash coat the noble metal physical isolation by making noble metal before being coated on base material at wash coat.By use the wash coat of different oxides and/or noble metal is arranged, the component of catalyst system and catalyzing is separated.Other benefit of this technology comprises control noble metal/base metal ratio and improves the dispersion of noble metal.This technology can be used for the present invention.Therefore, in a kind of preferred embodiment, the present invention relates to a kind of catalyst substrates, it comprises nSiRF-C, at least two kinds of catalytic metals and wash coat, and wherein said two kinds of catalytic metals are by physical isolation.

Isolate the wash coat example: isolate wash coat and at first be used for the automobile three-way catalyst.An example of this catalyst is three metal systems that comprise platinum, palladium and rhodium.The ground floor of catalyst is by Pd/Al ₂O ₃Constitute.Second (surface) layer is made of Rh/Pt/Ce-Zr.This design prevents to generate palladium-rhodium alloy, and this will make catalyst structure.

Alundum (Al or aluminium oxide are the base stocks of emission control catalyst wash coat.γ crystal structure (γ-the Al of high surface ₂O ₃) be used for catalyst and use.Be characterised in that the purity height.Al ₂O ₃In exist some element may influence its heat endurance, existing disappear long-pending also have positive.Al ₂O ₃In have minor N a ₂O strengthens the sintering of aluminium oxide as flux.On the contrary, comprise La ₂O ₃, SiO ₂, BaO and CeO ₂Have the effect of stable aluminium oxide surface area and reduce its sintering velocity simultaneously at interior several metal oxides.The aluminium oxide of stabilisation is commercially available.

In other embodiment, ceria or ceria are the components of catalyst wash coat, and for example addition is not more than 25%.In other embodiment, the addition of ceria is about 5%, 10%, 15%, 20% and 25%.Ceria is the important co-catalyst in the Vehicle Emission Control catalyst.The effect of ceria in three-way catalyst is storage oxygen, and this can pass through at Ce ⁴⁺And Ce ³⁺Between circulation realize.Other effect that ascribes ceria to comprises stable aluminium oxide, promotes steam reforming reaction, promotes noble metal to disperse and promotes the noble metal reduction.

Some diesel oxidation catalyst prescription comprises the ceria of top load.The effect of ceria is the solubility organic fraction catalytic oxidation/cracking that makes diesel engine particles.

The ceria of high surface can be by for example calcining cerium compound production.The BET surface area of ceria can be up to 270m ²/ g.Other embodiment for example in three-way catalyst, is used about 150m ²The ceria of/g surface area.The high-temperature stable kind that can tolerate 900-1000 ℃ has about 6-60m ²The surface area of/g is applicable to the present invention.

In other embodiment, catalyst substrates of the present invention or filtering substrate also comprise zirconia.In some embodiment, zirconia improves the heat endurance of base material.

Titanium dioxide is used as inertia non-sulfuric acid carrier with some diesel catalytic converters.Two kinds of important crystal structures of titanium dioxide comprise anatase and rutile.Anatase form is used very important for catalyst.It has 50-120m ²The highest face temperature of/g is long-pending, and it is heat-staple being not more than 500 ℃.Rutile structure has 10m ²The low surface area that/g is following.Change into rutile at about 550 ℃ of anatases, cause catalyst structure.In another embodiment of the present invention, catalyst substrates comprises nSiRF-C (preferred AETB or OCTB), catalyst and titanium dioxide.

Zirconia can be used as heat stabilizer and the ceria co-catalyst in the automobile three-way catalyst, also can be used as the non-sulfuric acid component of diesel oxidation catalyst wash coat.Zirconic BET surface area is 100-150m ²/ g.Discharge its surface area rapidly at 500-700 ℃.Use various doping agents to comprise that La, Si, Ce and Y can obtain better heat endurance.

Zeolite is synthetic or naturally occurring aluminium silicate compounds, and clear and definite crystalline texture and aperture are arranged.The size of zeolite pore between 3 and 8 , falls in the molecular dimension scope usually.Prevent that the bigger molecule of any cross-sectional area from entering the duct of zeolite cages.Therefore, zeolite is commonly referred to molecular sieve.Zeolite is characterised in that the specific area height.For example, the surface area of ZSM-5 zeolite is about 400m ²/ g.The surface area of modenite is about 400-500m ²/ g.Most zeolites are heat-staple being not more than 500 ℃.

The zeolite of some catalytic applications and metal cation carry out ion-exchange.Earlier with comprising NH ⁴⁺(NH ₄NO ₃) the aqueous solution handle the zeolite (NH that acid type zeolite (HZ) forms the ammonium exchange ⁴⁺Z ^-).Handle the zeolite (MZ) that forms metal exchange with the salting liquid that comprises catalysed cationic then.

Zeolite is excellent sorbing material because of its repeatable and determine pore structure.In comprising drying, purification and separate, many application are used as adsorbent.Synthetic zeolite also is used as catalyst in petrochemistry processing.

In recent years, the application of zeolite in Exhaust Control for Diesel Engine increases day by day, both as catalyst (SCR, poor NOx catalyst), again as adsorbent (capturing hydrocarbon in the diesel oxidation catalyst).

Should understand other embodiment of the present invention and comprise any concrete base material embodiment described herein, these base material embodiments also comprise any concrete wash coat embodiment.

Storage oxygen oxide

In another embodiment, catalyst substrates of the present invention or filtering substrate also comprise storage oxygen oxide.Storage oxygen oxide is CeO for example ₂Have oxygen storage capacity (hereinafter being abbreviated as " OSC "), promptly occlusion oxygen and release are by the ability of occlusion oxygen.More specifically, add CeO ₂Regulate the oxygen concentration of gaseous atmosphere, thereby make oxygen excessive in the gaseous atmosphere be occluded in CeO at oxygen enrichment state (be poor fuel state, can abbreviate " poor state " as) ₂With the help catalytic converter NOx is reduced into N in the crystal structure ₂, to help catalytic converter CO and HC are oxidized to CO and in gaseous atmosphere, discharge by the oxygen of occlusion at rich CO and/or rich HC state (be fuel-rich state, can abbreviate " rich state " as) ₂And H ₂O.Therefore, add CeO ₂The catalytic activity of catalyst substrates is improved.Other storage oxygen oxide comprises Pr ₆O ₁₁Deng, as US 6,576, disclosed in 200.Other embodiment comprises any concrete base material embodiment described herein, and the embodiment of these base materials also comprises for example CeO of storage oxygen oxide ₂

The SOx oxidation

In the presence of some metallic catalyst especially platinum, the sulphur that fuel for example exists in the diesel fuel changes into SOx, and SOx may produce for example fumes of sulphuric acid of environmentally harmful sulphur compound in waste gas then.Usually under about 350-450 ℃ higher EGT, form at most sulfate on the platinum catalyst.Though urgently need remove desulfuration from gasoline and diesel fuel prescription, during transition, catalyst formulation has attempted as much as possible to reduce this problem.

The typical platinum catalyst of Engelhard exploitation is by 5-150g/ft ³Ratio is 5: 1 Pt/Rh and 30-1500g/ft ³MgO forms (US 5,100,632 (Engelhard Corporation)).This catalyst can be immersed on the base material from group water solution.The filter that scribbles catalyst is preferred for 375-400 ℃ EGT and regenerates.The effect of rhodium is to suppress SO in the above-mentioned prescription ₂Catalytic oxidation, thereby suppress sulfate mask in the catalyst.

In some embodiment, thereby catalyst substrates of the present invention can address these problems by the thermal decomposition that for example has improved heat distribution minimizing catalyst.

Catalyst poisoning is the major reason of catalyst structure.Catalyst poisoning may take place when making the catalytic site chemical passivation or causing the catalytic surface fouling in the material that exists in the waste gas.Waste gas toxicity from internal combustion engine may come from lubricating oil component or fuel.

Between the different catalysts material or the interaction between catalyst material and the carrier component be the catalyst structure of another temperature-induced mode.Example is rhodium and CeO in the automobile three-way catalyst ₂Between reaction.This type of problem can reduce with physically-isolated alternative carrier of reactive component and the special fix-up washcoat layer technology of making known in the art.

Another advantage of the present invention is that nSiRF-C can make incompatible component physical isolation in the zones of different pumping, perhaps can use by the stacked film configuration, and inconsistent component is in the film base material that separates.

Because of corroding and wearing and tearing cause the wash coat Physical Loss or Damage, also catalyst structure may take place.Because thermal expansion is poor between high cycle speed, variations in temperature and wash coat and the host material, this mechanism may also be important for emission control catalyst.

The catalyst cover layer

During some is used, make NOx transform salify with adsorber catalyst, salt can manually be removed in regeneration technology then.But exist sulphur can cause generating insoluble SO in the fuel ₄Salt such as barium sulfate may form the protection coating and its efficient is reduced on catalyst.The advantage of certain embodiments of the invention is that described catalyst substrates reduces because of the sulfate coating causes efficient not too easily.

In another embodiment, catalyst substrates of the present invention or filtering substrate also comprise the protection coating that is applicable to pottery.For example, a kind of so suitable protection coating is disclosed in US 5,296, and in 288, the disclosure all is incorporated herein for reference.This coating is called the protection coating (PCC) that is used for ceramic material.The another kind of relevant coating that is fit to can Emisshield ^TMThe form acquisition (WessexIncorporated, Blacksburg, VA).Emisshield ^TMIn the radiance of radiation agent reinforcing material, especially at high temperature.In addition, the protection coating can reduce the infringement from external impact and abrasive forces.The coating that is fit to is disclosed in US 5,702,761 and 5,928,775 (DiChiara, Jr. etc.), and US 5,079,082 (Leiser etc.) in, these openly are incorporated herein for reference.Described coating can use with one or more concrete filtrations described herein and catalyst substrates.

In some embodiment, catalyst substrates or filtering substrate are heat shock resistance and thermal cycle infringement.But some base material is soft relatively, may suffer damage because of external impact and abrasive forces.For reducing this infringement, in a kind of preferred embodiment, catalysis of the present invention or filtering substrate also comprise one or more layers protection coating of substrate surface (preferred outer surface).The example of the protection coating that is fit to is disclosed in US 5,702,761 and 5,928,775, and US 5,079,082 in, these openly are incorporated herein for reference.Therefore, in a kind of preferred embodiment, the invention provides have the porosity higher than traditional base material, the base material of attributes such as higher permeability and enough hardness.Described coating can use with one or more concrete filtrations described herein and catalyst substrates.

Pressure drop

The present invention also provides the base material that catalytic converter and particulate filter pressure drop are improved.Therefore, in some embodiment, base material of the present invention can provide to be removed and/or filtering exhaust and do not have the accumulation of tangible back pressure or back pressure accumulation than conventional catalyst and the low means of particulate filter.

Waste gas flows through conventional catalytic converter and produces a large amount of back pressures.Back pressure accumulation in the catalytic converter is the important symbol of catalytic converter success.If catalytic converter partly or entirely stops up, then will limit gas extraction system.Back pressure accumulation subsequently will cause engine performance (for example power and moment of torsion) and fuel economy sharply to descend, if stop up seriously, even may cause stopping working behind the engine start.The tradition trial expense that reduces disposal of pollutants is very high, because have material and repacking or manufacturing that the original engine cost of suitable filter is arranged.

In some embodiment, base material of the present invention has the attribute of generation or littler pressure drop lower than the traditional base material that uses in catalytic converter or the particulate filter.The accumulation that the present invention makes cigarette ash in the particulate filter in some embodiment still less, can make under some situation change filter need frequency ratio conventional particles filter low.

The specific embodiment

The invention still further relates to the specific embodiments of the above catalysis and filtering substrate.Specific embodiments comprises base material, and described base material comprises (perhaps formed or mainly be made up of it by it alternatively) nSiRF-C and catalyst.Another embodiment is the filtering substrate that comprises nSiRF-C and a plurality of passages.

For example, some embodiment of base material has multiple above-mentioned attribute.In other embodiment, base material of the present invention has 2,3,4,5,6,7,8,9 in the above-mentioned attribute or 10 kind.Specific embodiments can comprise any combination of attribute.Further specify described catalyst substrates by following non-limiting specific embodiments.

In a kind of embodiment, base material of the present invention comprises the nSiRF-C composite, and this composite porosity is about 96% to about 99%, and density is about 10 to about 14lb/ft ³, have a plurality of passages that wall flows configuration; Has catalyst alternatively.

In a kind of embodiment, base material of the present invention comprises the nSiRF-C composite, and this composite comprises aluminium oxide boron oxide silicon dioxide fibre, silicon dioxide fibre and alumina fibre, and porosity is about 96% to about 99%, and density is about 10 to about 16lb/ft ³, preferred about 10,11,12,13,14,15 or 16lb/ft ³, have a plurality of passages that wall flows configuration; Has catalyst alternatively.In other embodiment, described base material also comprises wash coat, preferably the aluminium oxide or derivatives thereof.

In another embodiment, base material of the present invention comprises one or more the base material with following attribute: hot strength is about 100 to about 150, preferred about 130 to about 140,133psi more preferably from about; Thermal conductivity be about 0.5 to about 0.9, preferred about 0.7 to about 0.8,0.770BTU-ft*/hr ft more preferably from about ²; Thermal coefficient of expansion is about 1 to about 5 * 10 ^-6, about 1 to about 3 * 10 ^-6, more preferably from about 1.95 * 10 ^-6(77 -1000  test); Averag density be about 15.5 to about 17, preferred about 16 to about 16.8,16.30/lb/ft more preferably from about ³With optional catalyst.

In another embodiment, base material of the present invention comprises one or more the base material with following attribute: hot strength is about 50 to about 70, preferred about 60 to about 65,63psi more preferably from about; Thermal conductivity be about 0.5 to about 0.9, preferred about 0.7 to about 0.8,0.770BTU-ft*/hr ft more preferably from about ²; Thermal coefficient of expansion is about 1 to about 5 * 10 ^-6, about 1 to about 3 * 10 ^-6, more preferably from about 1.77 * 10 ^-6(77 -1000  test); Averag density be about 7 to about 9, preferred about 8.2 to about 8.6,8.40/lb/ft more preferably from about ³With optional base material.

In another embodiment, base material of the present invention comprises one or more the base material with following attribute: hot strength is about 60 to about 80, preferred about 70 to about 79,74psi more preferably from about; Thermal conductivity be about 0.5 to about 0.9, preferred about 0.7 to about 0.8,0.765BTU-ft*/hr ft more preferably from about ²; Thermal coefficient of expansion is about 1 to about 5 * 10 ^-6, about 1 to about 3 * 10 ^-6, more preferably from about 1.84 * 10 ^-6(77 -1000  test); Averag density be about 9 to about 11, preferred about 9.5 to about 10.5,10lb/ft more preferably from about ³With optional catalyst.

The another kind of catalyst substrates that is fit to of the present invention is nSiRF-C described herein; And catalyst, wherein said catalyst comprises: with the pre-carrier that mixes of cupric oxide (CuO); At least a noble metal that is selected from platinum (Pt), palladium (Pd), rhodium (Rh) and rhenium (Re) is as major catalyst, and wherein said at least a precious metal doping is on the surface of described pre-doping carrier; Be selected from antimony oxide (Sb ₂O ₃), bismuth oxide (Bi ₂O ₃), tin ash (SnO ₂), and their at least a metal oxide of mixture as co-catalyst, wherein said at least a doped metallic oxide is on the surface of described pre-doping carrier.This catalyst is described in US 6,685, and in 899, the document all is incorporated herein for reference.

In a kind of embodiment, base material is applicable to and is placed on exhaust manifold catalytic converter before relevant with waste gas stream in the motor head.

Other embodiment of catalyst substrates comprises catalyst substrates, and catalyst substrates comprises the nSiRF-C composite with approximate attribute shown in the following table.

	Embodiment 1	Embodiment 2	Embodiment 3
				Thermal conductivity	4-100×10 -2W/m-K	5-7×10 -2W/m-K	6.04F-02W/m-K
Specific heat	10-150J/mol K	600-700×10 -2J/kg-K	640×10 -2J/kg-K
				Density	.05-5gm/cc	0.1-0.3gm/cc	0.2465gm/cc
Radiance	.68-.97	0.7-0.92	0.88
				Axial strength	1.5-3.5MPa	2-3MPa	2.21Mpa
Noise attentuation under the 3500rpm	40-100db	70-80db	74db
				Porosity	80-99％	97-98％	97.26％
Permeability	At least 600	900-∞cd	1093-∞cd
				Recovery time	0.5-1.5 second	0.6-0.9	0.75 second
Surface area		70,000-95,000in 2	88,622in 2
				Fusing point	1700-5000	3000-4000℃	3,000℃
Thermal expansion (CTE)	0.001×10 -6-9×10 -6	0.1×10 -7-0.4×10 -7	0.25×10 -71/C

Another specific embodiments relates to a kind of catalyst substrates, and it comprises nSiRF-C described in table 1; Be selected from palladium, platinum, rhodium, their derivative, and their catalyst of combination.

The preferred substrates porosity that comprises senior non-woven refractory fibre is 90% to 98%, and the value of radiance is between 0.8 and 1.0.

In a kind of embodiment, filtering substrate of the present invention comprises or mainly is made up of nSiRF-C, the arrival end and the port of export before also comprising, approach and the intersection vertically extending wall section of porous and the matrix of horizontal-extending wall, it defines a plurality of passages that extend with vertically basic and the mode of being parallel to each other between the preceding arrival end and the port of export; Before arrival end comprise first sector hole that stops up along the part of its length with non-gridiron pattern pattern and second sector hole that stops up with the gridiron pattern pattern, the hole that second section gridiron pattern of boring ratio that first section non-gridiron pattern stops up stops up is little.This configuration further describes at US6, and in 673,414, it all is incorporated herein for reference.First section hole is no more than 3/4ths may be not blocked.Perhaps first section hole be no more than half may be not blocked.Perhaps, first section hole be no more than 1/4th may be not blocked.

Will also be understood that the present invention relates to by or the embodiment mainly formed by the restriction of various embodiments.Therefore, for example, a kind of embodiment has been described as comprising the catalyst substrates of nSiRF-C and catalyst, be interpreted as the present invention also comprise by or the catalyst substrates mainly formed by nSiRF-C and catalyst.

The method of catalytic reaction and filtration

Another aspect of the present invention relates to a kind of method of catalytic reaction, and comprising provides catalyst substrates of the present invention; Flow through and/or pass catalyst substrates from catalyst substrates under the temperature that is enough to the described reaction of catalysis with guiding fluid stream.Preferred reaction makes pollutant change into the uncontamination thing.For example, catalyst substrates makes carbon monoxide change into carbon dioxide in a kind of embodiment.

Described catalysis process is finished with the base material of the thermal boundary material that comprises aluminium oxide enhancing described herein.

In a kind of preferred embodiment, base material comprises suitable catalyst.

In a kind of embodiment, the present invention relates to a kind of method of filtering exhaust, comprise providing filtration of the present invention as mentioned above or catalyst substrates and guiding fluid for example to flow gas or liquid by described base material, wherein said gas comprises particle.

In another embodiment, this method also comprises burns the particle that leaches.Burning the particle that leaches makes the particle of accumulation mainly change into the uncontamination thing.

The present invention especially uses with Diesel engine in this respect.On the other hand, the present invention relates to a kind of filter method, wherein said filtration utilizes diesel particulate filter.

Diesel engine (compressing independent fire fuel) is subjected to the sifting of the whole world to its toxic emission recently, also contains a large amount of deleterious particles except that toxic gas.The response of manufacturer is to use known catalytic converter technology on Diesel engine.Regrettably, the physics and the economic restriction of conventional catalytic converter have been surpassed about the regulations of discharge standard.The difference of diesel emission and gasoline exhaust is to produce more substantial particle.For this reason, be used for that toxic emission is caught, the prior art of burning and oxidation is not enough to observe strict emission control standards.

Most of buses are that the diesel engine particles trap [" DPTs "] with 85% efficient is made or improved.The DPTs cost is very high, very complicated, fuel economy is lower and durability is low.Further regulations require to meet in 2010 100%, only can not satisfy these management expectancys with DPTs.The high temperature of engine or waste gas makes the particle can be in short time of staying internal combustion.Filter moves to more close engine chamber or increases auxiliary thermal source can provide more heat.Thereby need such filter: (1) can place excessive temperature promptly more than 500 ℃, for example near the combustion chamber; (2) more vibration resistance is degenerated; (3) still keep or improve the combustion efficiency of particle.Even do not having to realize under the situation of catalyst that the ability of particle burning also can be a lot of in saving aspect catalyst and the coating cost.

In case filter is caught particle (for example cigarette ash), just need in the presence of oxygen, fully heat up and make particle completing combustion.Can utilize the existing temperature of combustion gas and/or provide auxiliary thermal source to realize the burning of particle.During the used time of burning particles thing under this temperature is called required " time of staying ", " recovery time " or " burnouting ".The time of staying of particle in the base material hole, short changing into reduced the accumulation that plugging hole occurs, and this accumulation may cause the air-flow back pressure to increase, and this needs extra Energy Efficient running.Thereby the time of staying weak point be preferred.

US 5,611, and 832 (Isuzu Ceramics Research Institute Co. has enumerated a kind of DPT of routine in Ltd.), wherein discloses the DPT that is used for from the waste gas collecting granules of diesel engine emissions.This DPT filter is weaved inorfil and is placed woven wire therebetween to constitute by what cover with silicon carbide ceramics.

Other purposes of filtering substrate or catalyst substrates comprises and can remove or leach pollutant and impurity from fluid stream, for example: dust/cigarette ash, cigarette, pollen, fluid, bacterium/virus, smell, oil, VOC, liquid, methane, ethene and various other chemical substance comprise 188 kinds of those chemical substances that " poisonous air pollutants " are listed as EPA.

Catalytic reaction and/or the method for filtering fluid can be used for many industry or application, particularly following one or more: aerospace industry; Asbestos; Pitch covers and processing; Automobile and light truck (face coat); The waste disposal of benzene class; Shipbuilding; Brick and Application in Building; Clay product is made; Cellulose products is made; Carboxymethyl cellulose is produced; Cellulose ether is produced; The roughage dressing is made; Glassine paper is produced; Chromium is electroplated; Coke oven: push, quench and complete battery; Coke oven; Gas turbine; The agent of degreasing organic washing; Dry-cleaning; Between Engine Block Test or station; Cloth print, coating and dyeing; Ferroalloy is produced; Flexible polyurethane foams; Manufacturing operation; Flexible polyurethane foams is produced; Friction goods is produced; Gasoline distributes (first order); General supply; General MACT; The hazardous waste burning; Dangerous organic NESHAP; Hydrochloric acid is produced; Industry, commerce and public organizations' boiler; The industrial cooling tower process heaters; Steel plant; Iron foundry's (face coat); The leather finish operation; Lime is produced; Tape; Nutritious yeast is produced; Sea-freight ship loading operation; The mercury cell chlor-alkali plant; Metal-cored (face coat); Metal can (face coat); Metallic facility (face coat); Mineral wool product; Mix the coating manufacturing; Various metal parts and goods; The MSW landfill; Natural gas transmission and storage; The operation of waste recovery outside the venue; Oil and gas is produced; Organic liquid distributes (non-gasoline); Paper and other fabric (face coat); Pesticide activity component is produced; Oil plant; Pharmaceutical production; Phosphoric acid/phosphate fertilizer; Plastic components (face coat); Polymer and resin; The PPG product; Polybutadiene rubber; Polysulfide rubber; Phenolic resins; PET; Polyvinyl chloride and copolymer production; Portland cement is produced; Primary aluminum is produced; Former lead smelting; Native copper; Former magnesium refining; Printing/publication; Publicly-operated processing operation (POTW); Paper pulp and paper (non-burning) MACT I; Paper pulp and paper (non-chemically) MACT III; Paper pulp and paper (Combustion Source) MACT II; Paper pulp and paper are pulverized; Reciprocating internal combustion engine; Refractory product is produced; The reinforced plastics composite is produced; Secondary aluminium; The reviver smelting furnace; Semiconductor is made; Zao Chuan ﹠amp; Steamer is repaired; The scene is remedied; Be used to produce the solvent extraction of vegetable oil; Steel pickling-HCL technology; The processing of taconite iron ore; The tetrahydrochysene benzaldehyde is produced; Tire production; Wet shaping fiber; The production of pad; Timber products; Wood furniture; With the wool fiber glass production.The fixed discharge source of EPA control is adopted in these industry and application usually.

Other purposes that is fit to comprises filtration or the catalytic process in following one or more application: automobile (dust/cigarette ash, smell, oily filtration, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Water jet (dust/cigarette ash, smell, oily filtration, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Snowmobile (dust/cigarette ash, smell, oily filtration, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Puffer (dust/cigarette ash, smell, oily filtration, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Motorcycle (dust/cigarette ash, smell, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Removable Diesel engine (dust/cigarette ash, smell, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Fixing Diesel engine (dust/cigarette ash, smell, oily filtration, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Power station (dust/cigarette ash, smell, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Refinery's (VOC, other chemical substance (gaseous state, solid-state or liquid)); And chemistry and pharmacy (dust/cigarette ash, bacterium/virus, smell, oily filtration, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)).

In addition, other catalysis and/or filtration application are included in following one or more field and use base material of the present invention: discharging is incinerated in agricultural and forestry; Bakery's (dust/cigarette ash, cigarette, smell, VOC, other chemical substance (gaseous state, solid-state or liquid)); Biomedicine fluid filters; Winery and winery (smell); Cabin air (automobile, submarine, aerospace industry, aircraft) (dust/cigarette ash, cigarette, pollen, bacterium/virus, smell, VOC, other chemical substance (gaseous state, solid-state or liquid)); Clean room is used (dust/cigarette ash, cigarette, pollen, bacterium/virus, smell, oil, VOC, methane, other chemical substance); The commercial incineration discharged (smell, VOC, other chemical substance (gaseous state, solid-state or liquid)); The organic discharging of commercial toxicity; Drycleaner's's (VOC, other chemical substance (gaseous state, solid-state or liquid)); Volatility discharging (as the fuel gasification management); Fireplace; Barbecue (fast food) (dust/cigarette ash, cigarette, smell, VOC, other chemical substance (gaseous state, solid-state or liquid)); The health center; General fluid is filtered (drinking water treatment); Food processing and storage (smell, other chemical substance (gaseous state, solid-state or liquid)); Foundry Works's (smell); Fuel cell (VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Breathing mask (dust/cigarette ash, cigarette, pollen, bacterium/virus, smell, VOC, other chemical substance (gaseous state, solid-state or liquid)); The general VOC that is used to process/make uses (woodwork, coatings industry, textile industry etc.); Glass/ceramic; The greenhouse; Home appliances-cold (rechargeable utensil) (smell, oil, VOC, other chemical substance (gaseous state, solid-state or liquid); (water heater and the family heater) of home appliances-Re (smell, oil, VOC, other chemical substance (gaseous state, solid-state or liquid)); The HVAC sanitary installation; Hydroforming (VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); Medical medium; Office building; Oil/gasoline transportation; Other electricity-magnetic insulation (electricity-magnetic field); Paint uses; Gas station (smell, VOC); Polymer Processing (smell, VOC, other chemical substance (gaseous state, solid-state or liquid)); From hot gas and liquid, reclaim noble metal/catalyst; Restaurant smog; Sewage and biologic garbage (/ bacterium/virus, smell, VOC, methane, other chemical substance (gaseous state, solid-state or liquid); The slaughterhouse; Fumatory (dust/cigarette ash, cigarette); Sound insulation; Swimming pool; The tanning chamber; Tunnel and parking lot (dust/cigarette ash, smell, VOC, methane, other chemical substance (gaseous state, solid-state or liquid)); And incinerating waste material (dust/cigarette ash, smell, VOC, other chemical substance (gaseous state, solid-state or liquid)).

The preparation method of catalysis or filtering substrate

On the other hand, the present invention relates to the preparation method of arbitrary base material described herein (catalysis or filtration).The invention still further relates to the preparation method of catalyst substrates of the present invention.On the other hand, the present invention relates to a kind of preparation method of diesel particulate filter.Available many methods described below prepare described base material.

An aspect of of the present present invention, catalyst substrates described herein can prepare with the nSiRF-C blank that is purchased.The nSiRF-C blank that is purchased is processed into suitable shape, form and size.Base material of the present invention can be applicable to that by the bulk material is processed into shape of the present invention prepares with the bulk that is fit to host material.Unprocessed block of material can be easy to cutting or be sawn into prefabricated shape, sand milling then, turning or be processed into final " semi-finished product (slug) " that wants shape.Though the composition of described host material is easy to restore to chemistry, heat and vibratory impulse, the hardness of described host material is low.This soft allows to instrument almost not or machining under the situation of small amount of resistance or wearing and tearing arranged.Although it is the hardness of described block of material is low and soft, very durable and be easy to processing, engraving or moulding.For example, in some embodiment, the Mohs' hardness scale of host material is between 0.5 and 1.0 (or Knoop hardness scale 1-22) usually, the softest is that the talcum Mohs' hardness is 1 (1-22 Knoop hardness), the hardest is that the diamond Mohs' hardness is 10 (8,000-8,500 Knoop hardnesses).Some prior art host material of other fit value is harder.For example, the Mohs' hardness of carborundum is 9-10 (2, the 000-2950 Knoop hardness).

Under the situation that traditional base material such as cordierite difficulty reduce than some, make blank moulding, sand milling, turning or machining, can form the semi-finished product that shape is not limit.Described machining can be included in turning cylinder on the lathe, saw out shape, sand milling with keyhole saw, band saw or binding goes out shape or polished surface or is usually used in other solid material and any other machining process known in the art.Described blank can be machined to very strict tolerance, and precision is identical with machining metal, timber or plastics.If want casting ingot in the cylindric mould of diameter at net shape, then machining only needs the cylinder blank cutting is become the thickness of wanting with sand milling.This technology also reduces substrate loss due to the excessive machining, and the preformed process is quickened.

In some embodiment, described base material front be shaped as circular 510, oval 520 and runway shape 530, as shown in Figure 5.Obviously, these shapes need not to be accurate.On the three-dimensional, described base material can be cylinder or flat substantially disc format.The design that has the right angle during some is used is not very effective.Though be easy to processing, proved square or had the design at angle to be rust and to corrode for example trap of snow melt salt of thing.Thereby in some embodiment, fillet is preferred for the shape of half-finished front.

Described blank can be used other known method moulding of band saw, binding, CNC or ordinary skill people.Described blank can further be shaped with artificial friction, lathe sand milling, belt sanding or track sand milling.Preferred vacuum is extracted the hole that airborne particulates prevent its plugging material out.And these particulates may enter the bearing of drilling machine and damage drilling machine, grind off and abrade bearing.The pottery dust is also very thin, may not be operated the person easily and sucks.

In another embodiment, the present invention relates to preparation method, comprise preparation nSiRF-C composite blank according to catalysis of the present invention or filtering substrate; Alternatively with described blank machining to form base material of the present invention.If blank is to prepare with the shape that is applicable to one or more technologies of the present invention, then blank may not be machined into difformity.In the case, the mould with suitable shape as described below prepares blank.Perhaps, described blank or base material can be machined into suitable shape.Further, as the back in greater detail, machining goes out a plurality of passages in described base material.

The preparation process of blank (or base material) comprises the known method for preparing these materials.Can adopt any known suitable blank or the preparation method of base material.For example, the method that is fit to is disclosed in US 4,148, in 962 and 6,613,255, these are open all be incorporated herein for reference.

As limiting examples, in a kind of embodiment, the step that preparation is fit to base material comprises:

With many fire-resistant silicon dioxide fibres, fire-resistant alumina fibre and the heating of fire-resistant aluminoborosilicate fiber;

Described fiber is mixed;

Wash described fiber;

Alternatively described fiber is cut into one or more length;

Make described chopped strand fusion or be mixed in the slurry;

Regulate the viscosity of described slurry, preferably by adding thickener;

Add dispersant;

Described slurry is added in the mould;

From described slurry, remove and anhydrate to form green compact;

Green compact are taken out from mould;

In baking oven, make the green compact drying, preferably to the temperature of about 500 , carry out drying about 250; With

In baking oven under about 2000-2500  the described green compact of heating, preferred preheating and increase progressively heating.

As mentioned above, then alternatively with described blank machining to form base material of the present invention.

In another embodiment, technology is included in also that machining goes out a plurality of passages in the base material.

In another embodiment, technology also is included in increases wash coat on the base material.

In another embodiment, technology also is included in increases catalyst coatings on the base material.

In another embodiment, after washing and adding thermal fiber, carry out the mixing of fiber again.

In another embodiment, use boron nitride in the process of preparation base material of the present invention again.

In another embodiment, use thickener again.The thickener and the dispersant that use in preferred this technology are removed from base material during heating steps substantially.For example, thickener and dispersion can be burnt in sintering process.

Base material 2510 is from the blank that weak point is cut and/or non-woven inorfil and adhesive produced by formation rigidity configuration.With blank machining or be processed into base material 2510 desired external dimensions.The inside of machining or processing base material 2510 is to provide desired surface long-pending configuration for example passage, wash coat or the catalyst of increasing then.Can on base material 2510, apply durable inorganic hardening coat 2511 by brushing, spraying, dip-coating or any other coating method commonly used.In addition, base material 2510 can comprise oxidation or the reducing catalyst by brushing, spraying, dip-coating or any other coating method commonly used coating.

In a kind of embodiment, catalysis of the present invention or filtering substrate comprise nSiRF-C; And coating, this coating comprises 23.0-44.0wt% SiO 2 powder, 25.0-45.0wt% colloidal silica, 19.0-39.0wt% water and one or more radiation agent of mixing, and described radiation agent is selected from four silicon borides, silicon hexaboride, carborundum, molybdenum disilicide, two tungsten silicides and zirconium diboride; The solids content of wherein said protection coating is 45-55wt%.This coating is disclosed in US5, in 296,288.

The present invention utilizes multiple senior non-woven sintering inorganic refractory fiber, those as existing among the AETB.Other material that is suitable for use in the present invention as nSiRF-C comprises that AETB-12 (consists of about 20%Al ₂O ₃, about 12% (14%B ₂O ₃, 72%Al ₂O ₃, 14%SiO ₂NEXTEL ^TMFiber) and about 68%SiO ₂); AETB-8 (consists of about 20%Al ₂O ₃, about 12% (14%B ₂O ₃, 72%Al ₂O ₃, 14%SiO ₂NEXTEL ^TMFiber), 68%SiO ₂); FRCI-12 (consists of about 78wt% silica (SiO ₂) and about 22wt% aluminoborosilicate (62%Al ₂O ₃, 24%SiO ₂, 14%B ₂O ₃)); And FRCI-20 (consists of about 78wt% silica (SiO ₂) and about 22wt% aluminoborosilicate (62%Al ₂O ₃, 24%SiO ₂, 14%B ₂O ₃)).

In a kind of preferred embodiment, the composition of described inorfil by or mainly fibrous by fiber silica, alumina fibre and aluminoborosilicate.In this embodiment, about 50-90% of fiber silica comprises inorfil mixture, alumina fibre accounts for about 5-50% of inorfil, and the aluminoborosilicate fiber accounts for about 10-25% of inorfil mixture.In some embodiment, preparing the used fiber of base material of the present invention can existing crystalline phase, glassy phase is arranged again.

Other fiber that is fit to comprises the aluminoborosilicate fiber, preferably be contained in aluminium oxide in about 55 to the about 75 heavy % scopes, less than about 45 to (preferably less than 44 to greater than 0) heavy % scope greater than 0 silica and less than 25 to (boron oxide in preferred about 1 to the about 5 heavy % scopes is respectively with Al greater than 0 ₂O ₃, SiO ₂, and B ₂O ₃Form is calculated based on theoretical oxide.The aluminoborosilicate fiber preferably has at least 50 heavy % crystallizations, more preferably at least 75%, most preferably from about 100% (being crystalline fibers).The aluminoborosilicate fiber of grading is commercially available, for example with trade name " NEXTEL 312 " and " NEXTEL 440 " available from 3M company.In addition, the aluminoborosilicate fiber that is fit to can be as disclosed preparation among the US 3,795,524 for example, and its content all is incorporated herein for reference.

Other fiber that is fit to comprises aluminosilicate fiber, normally crystallization, and it is included in about 67 aluminium oxide and silica in about 33 to about 23, for example 31,29,27 and 25 heavy % scopes to about 77, for example 69,71,73 and 75 heavy % scopes.The aluminosilicate fiber of sizing is commercially available, for example with trade name " NEXTEL 550 " available from 3M company.In addition, the aluminosilicate fiber that is fit to can be as disclosed preparation among the US 4,047,965 (Karst etc.) for example, and its content is incorporated herein for reference.

In other embodiment, prepare the used fiber of base material of the present invention and comprise interpolation Y ₂O ₃And ZrO ₂α-Al ₂O ₃, and/or add SiO ₂α-Al ₂O ₃(form α-Al ₂O ₃/ mullite).

Many SPECIAL MATERIALs can be used for preparing catalyst substrates.In a kind of embodiment, prepare base material material therefor of the present invention and comprise fire-resistant silicon dioxide fibre and fire-resistant aluminoborosilicate fiber (perhaps form or mainly form) by it by it.In another embodiment, preparation catalyst substrates material therefor comprises fire-resistant silicon dioxide fibre, fire-resistant grade aluminum oxide fiber and adhesive, preferred boron oxide or boron nitride powder.

In a kind of embodiment, catalyst substrates of the present invention comprises thermal boundary (" AETB ") material or the known similar material (perhaps formed or mainly be made up of it by it) of those of ordinary skills that aluminium oxide strengthens.The AETB material is known in the art, be described in Leiser etc. more fully, " Options for Improving Rigidized Ceramic Heatshields ", Ceramic Engineering and Science Proceedings, 6, No.7-8, pp.757-768 (1985) and Leiser etc., " Effect of Fiber Size and Composition onMechanical and Thermal Properties of Low Density Ceramic CompositeInsulation Materials ", NASA CP 2357, among the pp.231-244 (1984), these documents all are incorporated herein for reference.

In another embodiment, catalyst substrates comprises ceramic tile, the thermal boundary (AETB) that the aluminium oxide of glass (RCG) coating of solidifying if any toughness reinforcing monolithic fibrous insulation (TUFI) and/or reaction strengthens.This type of material is known in the art.

The another kind of material that is fit to is cellulosic refractory insulation (FRCI).In a kind of embodiment, AETB is by aluminium oxide boron oxide silica (being also referred to as aluminium oxide-boron oxide-silica, aluminoborosilicate and sial borate) fiber, silicon dioxide fibre and alumina fibre.A kind of known application of AETB be on space shuttle as the external application patch block, it is desirable being used for that space shuttle reentries.AETB has the fusing point height, thermal conductivity is low, thermal coefficient of expansion is low, ability is heated and vibratory impulse, density is low and porosity and the very high attribute of permeability.

In a kind of embodiment, first component of AETB is an alumina fibre.In the preferred embodiment of the present invention, aluminium oxide (Al ₂O ₃Or alundum (Al, for example SAFFIL) normally about 95 to the about 97 heavy % aluminium oxide and about 3 to the about 5 heavy % silica of commercial form.In other embodiment, also can use the lower aluminium oxide of purity, for example 90%, 92% and 94%.In other embodiment, also can use the higher aluminium oxide of purity.Aluminium oxide can be by extruding or reel off raw silk from cocoons method production.At first, the solution of preparation precursor substance.Cause slow and progressive polymerization process,, thereby make single precursor molecule in conjunction with forming bigger molecule for example by control pH.Along with the carrying out of this process, mean molecule quantity/size increases, thereby causes solution viscosity along with the time increases.Under the viscosity of about 10 centipoises, solution becomes gets slightly gluing, can draw or reels off raw silk from cocoons fiber.Under this state, also can extrude fiber by die head.In some embodiment, the average diameter of fiber is in about 1 to 6 micron scope, but fiber bigger and more minor diameter also is applicable to the present invention.

In a kind of embodiment, second component of AETB is a silicon dioxide fibre.In some embodiment, silica (SiO ₂, for example Q-fiber or quartz fibre) contain and surpass 99.5 heavy % amorphous silicas, impurity content is very low.More low-purity for example 90%, 95% and 97% silica also be applicable to the present invention.In some embodiment, use and to have low-density (2.1-2.2g/cm for example ³), high-fire resistance (1600 ℃), lower thermal conductivity (about 0.1W/m-K) and near the amorphous silica of zero thermal expansion.

In a kind of embodiment, the 3rd component of AETB is an aluminium oxide boron oxide silicon dioxide fibre.Under some situation, aluminium oxide boron oxide silicon dioxide fibre (3Al ₂O ₃2SiO ₂B ₂O ₃, for example NEXTEL 312) and be generally 62.5 heavy % aluminium oxide, 24.5 heavy % silica and 13 heavy % boron oxides.Certainly, the definite percentage of each composition can change in the described aluminium oxide boron oxide silica.Mainly be amorphous products, but also can contain the mullite of crystallization.Aluminium oxide boron oxide silicon dioxide fibre that is fit to and preparation method thereof is disclosed in for example US3, and in 795,524, its instruction all is incorporated herein for reference.

Other material that is suitable for use in the present invention as nSiRF-C comprises: (it consists of about 20%Al to AETB-12 ₂O ₃, about 12% (14%B ₂O ₃, 72%Al ₂O ₃, 14%SiO ₂NEXTEL ^TMFiber) and about 68%SiO ₂); (it consists of about 20%Al to AETB-8 ₂O ₃, about 12% (14%B ₂O ₃, 72%Al ₂O ₃, 14%SiO ₂NEXTEL ^TMFiber), 68%SiO ₂); (it consists of about 78wt.% silica (SiO to FRCI-12 ₂) and 22wt.% aluminoborosilicate (62%Al ₂O ₃, 24%SiO ₂, 14%B ₂O ₃)); And FRCI-20 (it consists of about 78wt.% silica (SiO ₂) and about 22wt.% aluminoborosilicate (62%Al ₂O ₃, 24%SiO ₂, 14%B ₂O ₃)).

In a kind of preferred embodiment, the inorfil component by or mainly fibrous by fiber silica, alumina fibre and aluminoborosilicate.In this embodiment, about 50-90% of fiber silica comprises inorfil mixture, alumina fibre accounts for about 5-50% of described inorfil, and the aluminoborosilicate fiber accounts for about 10-25% of described inorfil mixture.

Except that the AETB fiber or replace the AETB fiber can use fiber like the fiber-like with AETB described herein.

Can be undertaken by two kinds of universal methods by the melt production fiber.First method relates to centrifugal reeling off raw silk from cocoons and combines with the gaseous state drawing-down.The glass flows of proper viscosity flow on the draw plate that rotates with the thousands of commentaries on classics of per minute from smelting furnace continuously.Centrifugal force is outwards invested the wall that reels off raw silk from cocoons that contains thousands of holes with glass.Glass is driven by centrifugal force once more by these holes, and before collecting by the thermal current drawing-down.

In second kind of fusion technology, be installed with in the heating tank of (depending on application) of hundreds of or thousands of holes to the bottom surface and infeed fusion gas.Glass flows is crossed these holes and is stretched, and forms single fiber.Fiber is merged into strand and is collected on the axle.

In a kind of embodiment, the AETB fibre blend in the slurry preferably comprises three kinds of compositions, comprises glass fibre, alumina fibre and aluminium oxide boron oxide silicon dioxide fibre.About 50-90% of the described inorfil mixture of described fiber silica comprises; Described alumina fibre accounts for about 5-50% of described inorfil mixture; About 10-25% of the described inorfil mixture of described aluminium oxide boron oxide silica comprises.In other embodiment, described slurry comprises and prepares the spendable any fibre blend of base material of the present invention as mentioned above.

In a kind of preferred embodiment, the fibre fractionation of described base material is the mixture of 64% amorphous silica, 21% aluminium oxide and 15% aluminium oxide boron oxide silicon dioxide fibre, uses trace for example 0.3 to 1.0mg/m ²Surfactant help to cast before and during the dispersion of staple in bulk in slurry.

In a kind of embodiment, the fiber in the slurry is mainly inorfil.Preferably in one embodiment, the present invention does not use any carbon in forming base material.

The alternative compositions that aluminium oxide-zirconium oxide fibres can be used as the 4th component or other fiber adds in the inorfil mixture.

Composite fibre

In the step of embodiment of the present invention, fiber is mixed.Many known fiber mixed methods all can be used for making fiber to mix.Example is adoptable high shear mixing.

Add thermal fiber

In the step of the present invention, make the fiber heating by known method.Earlier with the fiber heating so that chopped fibres more equably.Fiber wash after the heat treatment to remove all dusts, fragment and loose particles, is only stayed fiber in order to handling.

In a kind of preferred embodiment, fiber is carried out thermal cleaning.

Washing the fibre

In the step of the present invention, washing the fibre.In a kind of method for optimizing, washing the fibre makes fiber not contain dust and particulate substantially.In a kind of embodiment, silicon dioxide fibre is washed in acid removing impurity, rinsing, drying is heat-treated then and is given structural intergrity.

Prescind chopped strand

In another step of the present invention, fiber is prescinded.Being used for fiber of the present invention usually can loose or chopped strand form acquisition.The method of chopped fibres is known in the art.Majority method is to handle the continuity method of many fibers or thigh simultaneously.Typically, supplying products between one group of runner or rotary drum, one of them is supporting the cutting edge of regular spaces.When fiber is pulled and draws by cutting knife, be cut into certain-length.Though being formed the concrete manufacturing details of base by chopped strand still is proprietary, this technology is usually directed to one of two kinds of production mechanism: fusion and sol-gel.Preferably before finally prescinding, fiber is heat-treated.

Preferably, then fiber is cut into certain size.The fibre length that is fit to includes but not limited to about 0.1,0.2,0.3,0.4,0.5 or 0.6 inch.Other suitable length comprises 1/8 ", 1/4 " and 1/2 ".The size of optimum fiber is consistent.In another embodiment, form the fiber of catalyst substrates or filtering substrate and on average grow about 1 to 12 micron of 1/4 inch (one of about percentage rice), diameter, perhaps 1 to 6 or 10 to 12 micron, 3 microns of intermediate value fibre diameters.In a kind of preferred embodiment, do not add particulate matter, because it may block pores.Be applicable to that fiber of the present invention is commercially available, for example from 3M.Certainly, in other embodiment, use longer fiber.

Form slurry

In another step of the inventive method, preparation comprises the slurry of described fiber.Be not extruded ceramic or around the porous core tube winding yarn or fabric, described base material can pass through ordinary sol-gel method and prepare.Finish by method: the abundant mixed sols with inorfil and colloidal solution draws (by vacuumizing or the gravity stretching) to the fiber mould earlier, thereby produces colloidal sol base or green compact or blank.

Perhaps, can adopt the extrusion casint pressurization, wherein pressure is reduced to negative value or vacuum method.Vacuum method can form has the inorfil base that extremely-low density keeps its intensity simultaneously.Sol-gel process and pressurization or vacuum method are combined with and help produce unusual low density, and this is very useful for micro particle filtering.

Fiber is mixed.In some embodiment, slurry may contain 1 to 2 heavy % solid, and is almost mobile as water.Perhaps, described slurry can contain 0.5 to the about 5 heavy % solid of having an appointment.Other weight percent also can be accepted, as known in the art.

With high-shear mixer chopped strand is mixed.Preferably in slurry, use deionized water with avoid melting or use in the fiber unsettled impurity that becomes.In a kind of embodiment, but the pumping slurry by centrifugal cyclone to remove particulate glass and other pollutant, comprise high soda particle.

Perhaps, can in fiber slurry, add organic fiber or the particle that is no more than 30 heavy %.In the sintering stage of producing, described organic fiber volatilizes from goods or burns.The fiber burning stays the space, and overflowing for gas provides the path.Change the type and the ratio of polymer fiber, the permeability of customizable ceramic tile.The blank of producing by the method is a porous, thereby can be by introducing effectively cooling of venting.

Regulate viscosity

In another embodiment, viscosity is adjusted to suitable scope.The higher prevention fiber of viscosity " is paved ", promptly sets level or only is orientated with substantially horizontal direction.Can adding boron nitride, to come coated fiber as thickener be high-strength sintered preparing.In a kind of embodiment of the present invention, add boron nitride and in slurry, do not use aluminium oxide boron oxide silicon dioxide fibre.

Add dispersant

In a kind of embodiment, described method is included in and adds one or more dispersants in mixture or the slurry.

In a kind of embodiment of the present invention, in technical process of the present invention, in described slurry, add one or more surfactants.The consumption of surfactant is about 5 to about 10 heavy %.Use surfactant help to cast before and during the dispersion of staple in bulk in slurry, thereby prevent that the collection of filaments together.

In a kind of embodiment of the present invention, in slurry, add one or more catalyst as mentioned above.Add catalyst in this stage of this method, obtain the base material of catalyst soakage in porous material.In a kind of embodiment, this configuration does not need further washcoat coating or catalysis.

Molding

In a kind of embodiment, described slurry poured into form blank in the mould.The shape of mould can be any shape of wanting.In some embodiment, the shape of mould has generation the base material of the shape that is applicable to catalytic converter or particulate filter.For example, mould can be cylindrical shape.Perhaps, mould is a pentagon.Fiber preferably make the slurry can not sedimentation in mould, because can be set level.In a kind of embodiment, utilize vacuum aspiration to keep the porosity and the consistent in density of material in not sedimentation of fiber and the whole blank of maintenance.Can utilize the vacuum draw technology from the arrangement of many direction control fibers and the density of green compact.

As an example, 24in * 24in (576in of fillet is being arranged ²The blank of production catalysis or filtering substrate in the mould of) * 4in.Certainly, can produce the blank of greater or lesser size.

The material of mould can be any material stable under the situation of water to be arranged, including but not limited to metal or plastics.Other material that is fit to comprises aluminium, PLEXIGLAS and other synthetic material.Aluminium is long-term very durable, and the PLEXIGLAS material is cheap and be easy to machining.The permeable surface that is fit to carefully metallic sieve form obtains.Greater than about 50in ²Semi-permeable surface can preferably use backing or supporting construction sagging in some cases to prevent.

Some embodiment may need anaerobism during casting be oxygen-free environment.Oxygen-free atmosphere produces and to make the minimum and environment of reinforcing fibre combination uniquely of burning.The blank that soaks is put into for example big polybag in the chamber that is full of ammonia.Ammonia is the most frequently used, because its cost is low and be easy to get.Also can add nitrogen and/or hydrogen.Nitrogen is better than hydrogen, because hydrogen is active.In fact, as long as keep reduction and oxygen-free environment, can add any gas.Preferably provide gas to form the gel blank until the colloidal sol blank that soaks with constant flow.At this moment, close gas, the gel blank is exposed in the open, gas is overflowed.

Carbon or organic group article shaped can be used as the pore-forming rod and introduce in the green compact in the molding stage.When high temperature sintering, these rods can decompose and stay desired a plurality of passage.

Slurry dewatering

Produce in a kind of embodiment of blank, slurry is placed in the mould of sealing, and its at least one size is adjustable and at least one wall is semi permeable.Apply compression stress and by semi-permeable wall discharge water from slurry by adjustable wall, and collect fiber and make it bonding in semi-permeable wall.Continuing compression is billet size until meeting the requirements of preformed.The method is generally limited to simple geometry figure such as piece or cylinder.

Gravity is not enough usually as driving force, thereby needs to use vavuum pump.Vavuum pump adopts almost not to there not being pressure.Under some situation, utilize vacuum dehydration, but the suction that adopts is very small.Vacuum as the sensitive means of quickening dry run to avoid increasing density.The preferred vacuum aided that only adopts appropriateness.

Can prepare the more complicated blank of shape by other method, for example wherein the pressure head of slurry is placed on and remains on the semi-permeable template.Utilize vavuum pump to become low pressure in the infiltration die shape.This pressure reduction orders about water and collects fiber and make it bonding at this by the infiltration template.Keep this pressure reduction and want thickness until reaching.It is the highly application of bending that this technology is fit to the base material of wanting, is similar to final form or near the blank of its final form because can produce.

The vacuum rate (repeatedly) of injecting or mixing multiple (two or more) slurry prescription and change traction provides some zone finer and close and/or the blank in the different zone of rerum natura arranged than other zone.Described blank can have gradual change or different layer or the chemical composition cores different with density.Described blank can have one or more districts, and there are unique shape, position and required rerum natura in each district.Each district can change intensity, heat or electrical conductivity, catalyst tackability, thermal expansion, vibration or thermal shock, weight, porosity and permeability, sound attenuating or any other preferred character as required.

Adopt different slurry prescription and molding technology, also can make the blank layering.In addition, described blank is not limited to only parallel plane layer such as the layer on the cake, and can form the blank that has level, becomes angle, sphere, pyramid and free form layer or any other configuration known in the art.Should also be noted that the density that in this technical process, can change described blank when needing by chemistry and physical method.

Also can be by forming blank at the inboard or inner a plurality of blanks of placing any configuration (no matter being that solidify or uncured) of different chemical composition of another blank.Described core base can manually be put into blank or inject in-core.The result is the lower or higher one or more cores of density.The shape or the form of these cores and blank are not limit, and are the combinations of core layering.Even can produce core at in-core.Can repeat this process, number of times is not limit, and obtains the combination of unique number of the blank that shape do not limit as required.

The green compact drying

In the step of embodiment, the oven dry long enough time of the slurry in the mould is made it dehydration, promptly drive away any water that it may comprise.Can utilize the gravity discharge water.Can adopt micro-vacuum auxiliary.Certainly also can adopt other method known in the art.

From mould, take out green compact and make the green compact drying

In the step of embodiment of the present invention, from mould, take out green compact.Usually can enough do at blank and take out described blank when processing with activation.Perhaps, when enough doing with activation with machine operation, takes out blank described blank.

For example, enough do when processing, it is taken out from mould with activation when blank.In baking oven, make the blank drying then.Adopt enough low temperature to finish dehydration and to make fiber can keep its expection configuration substantially.Most preferably described temperature is enough to make as required the blank drying but is not enough to cause any of blank or any basically sintering.In another preferred embodiment, use the temperature of about 250-500  in this step.Again in another embodiment, make blank under about 180 ℃ temperature dry about 2 to about 6, preferred about 4 hours.Can adopt At All Other Times known in the art and temperature.

Can randomly make flakes in sol-gel adhesive (preferred aluminium oxide sol-gel binder), soak a period of time (for example several days) then in different temperatures, as known in the art, simultaneously blank with binder solution " siphon " (promptly absorbing) to blank.The adhesive that is fit to is known in the art, and may need to give preform structural intergrity and acceleration of sintering.Described blank can utilize single or multiple adhesive method to change the intensity and the conductivity of blank.Repeatedly applied adhesives will increase the intensity of blank but also may reduce or stop up hole.Can use any suitable adhesive.Described adhesive can be oxide adhesive such as SiO ₂Or Al ₂O ₃Described oxide adhesive also can be glass configuration, crystallization configuration or other inorganic bond.Available known technology and method applied adhesives, disclosed in 473 as US 3,549, its instruction all is incorporated herein for reference.

Green compact drying (sintering)

In another step of embodiment of the present invention, make the green compact heat cure.The temperature of heat cure or sintering is higher than the temperature that green compact drying adopted usually.In a kind of embodiment, through one hour or more a plurality of hours, preferred several hours temperature is increased progressively, until reaching temperature required.In a kind of embodiment, with the baking oven preheating and increase progressively and be heated to about 2000-2500 .Other temperature known in the art also is fit to.

In a kind of preferred embodiment, after the described adhesive gelatinization,, slowly be warming up to about 600  through about 5 hours then, blank is solidified by blank heating is continued about 4 hours to about 200 .Reach and keep after the described maximum temperature, make the blank fast quench.Final result is the inorfil blank of rigidity.The heat curing process of described blank used temperature, hardening time length, hardening heat and time, temperature increase progressively and increase progressively temperature and increase and also can change aspect the timing.

Blank lighted to provide make fiber-fiber contact sintering institute energy requirement, thereby form combination, substrate intensity is given in described combination.For example, the quantity that increases fiber-fiber contact can improve intensity.Increasing contact quantity increases density and distortion.Pore network is distortion more, and permeability is low more.Sintering does not make fibre fusion together, but makes it chemical bonding.In high temperature furnace, blank is heated gradually.Make the blank preheating, increase progressively then and be heated to about 2000-2500  until obtaining the density of wanting and fusion.Auxiliary chemical substance such as thickener are burnouted.Stay comprise sintered fiber or by or the base material mainly formed by sintered fiber.

In a kind of preferred embodiment, viscosity (thickener) chemical substance and dispersant are burnouted.

In other embodiment, carry out a plurality of curing schedules.Can improve the hardness of base material like this.

Can be according to density, intensity, porosity or the permeability of want fiber base or the variable in heat-resisting quantity adjusting drying and the curing process.In some embodiment, curing process can adopt repeatedly and solidify, and can change the time interval and the approach of heating and cooling.Blank is cooled off rapidly so that blank quenches or tempering.Described slurry can experience additional heat or other processing, as the density coating or repeatedly solidify and sintering.

Physical modification

In some embodiment of described method, to the blank coating catalyst.On base material, apply in a kind of method of catalyst, can form base material by the slurry that contains catalyst.Can adopt other to apply the appropriate methodology of catalyst.Another advantage of the present invention is to be surprised to find that can utilize the method that applies catalyst to other material to apply catalyst to the nSiRF-C material.

In another embodiment of the present invention, before molding, catalyst is added in the slurry.In the case, the formation catalyst is located immediately at the catalyst substrates on the single fiber that constitutes base material.In some embodiment, this method to base material interpolation catalyst provides the effective ways that make catalyst be dispersed in the in-core of catalyst substrates and do not have catalyst only to exist along conduit wall.In this embodiment, wash coat is unnecessary.

Machining

The regulation shape can be cut or be sawn into to the blank of undressed form, sand milling then, turning or be processed into final " semi-finished product " of wanting shape.Though the composition of this material is easy to restore to chemistry, heat, heat and vibratory impulse, in the preferred embodiment, hardness is extremely low.This soft allows to instrument almost not or machining under the situation of small amount of resistance or wearing and tearing arranged.Although it is the hardness of blank is low and soft in some embodiment, very durable and be easy to processing, engraving or moulding.The Mohs' hardness of material is between 0.5 and 1.0 (or Knoop hardness 1-22) usually, and the softest is that the talcum Mohs' hardness is 1 (1-22 Knoop hardness), and the hardest is that the diamond Mohs' hardness is 10 (8,000-8,500 Knoop hardnesses).For example, the Mohs' hardness of carborundum is 9-10 (2, the 000-2950 Knoop hardness).With respect to other known substance, described blank dead-soft and process or carve leicht fallen D/A as foamed polystyrene or light wood.

Described blank is plastic, sand milling, turning or machining, can form the semi-finished product that shape is not limit.Described machining can be included in turning cylinder on the lathe, saw out shape, sand milling with keyhole saw, band saw or binding goes out shape or polished surface or is usually used in other solid material and any other machining process known in the art.Described blank can be machined to very strict tolerance, and precision is identical with machining metal, timber or plastics.If want casting ingot in the cylindric mould of diameter at net shape, then machining only needs the cylinder blank cutting is become the thickness of wanting with sand milling.This technology also reduces substrate loss due to the excessive machining, and the preformed process is quickened.

Many possible front surfaces and rear surface shape are arranged, comprise circle 510, ellipse 520 and runway shape 530, as shown in Figure 5.On the three-dimensional, described base material can be cylinder or flat substantially disc format.The tradition base material is one of these three kinds designs.Right-angle design is not very effective.Though be easy to processing, proved square or had the design at angle to be rust and to corrode for example trap of snow melt salt of thing.Thereby fillet is preferred for half-finished front surface shape.

Described blank or base material or semi-finished product can be used other known method moulding of band saw, binding, CNC or ordinary skill people.Described semi-finished product can further form with artificial friction, lathe sand milling, belt sanding or track sand milling.Must vacuum extract the hole that unloaded particulate prevents its plugging material out.And these particulates may enter the bearing of drilling machine and damage drilling machine, grind off and abrade bearing.The pottery dust is also very thin, may not be operated the person easily and sucks.

The semi-finished product of moulding are in the present invention as base material.For catalytic applications, the surface area of base material is a key property.Surface area is the area summation that waste gas must pass during by waste gas filter.The surface area increase means that the space that is used between the pollutant taking place chemical reaction and catalysis and thermal process is bigger, makes the catalytic converter process faster and more effective.Speed and efficient can cause taking place hardly the obstruction to trouble of exhaust system does not take place to cause.

In a kind of embodiment, the total surface area of base material of the present invention is 83.58 square inches/cubic inch.It is much higher that this is converted into the cordierite sample that can be had suitable macro-size (for example diameter, length and width) by the area ratio that noble metal floods.But the calculating that should note this total surface area does not even comprise density, porosity and the permeability of different materials.

In a kind of example embodiment of the present invention, described base material is used for the diesel engine exhaust filtration system.Described base material forms with the AETB prescription, makes about 13 " * 13 " * 5 " blanks of density between 8 and 25 pounds/cubic feet.From described blank, cut out the cylindrical semi-finished product or the oval column semi-finished product of 6 inches of 5 inches high diameters with diamond point or tungsten carbide band saw.On spinning lathe (for right circular cylinder) or belt sander, these semi-finished product further are machined into to precision tolerance formation base material.

Drilling and passage in base material

In one embodiment of this invention, in filtration or catalyst substrates, form basically with respect to a plurality of longitudinally passages of expection air-flow.These channel parts or run through base material length fully.Fig. 5-14 illustrates the schematic diagram of some embodiments of the present invention of a plurality of passages for example.In some embodiment, passage and direction of fluid flow are angled.

The inner surface of these passages can have immersion coating to capture and to handle more multi-pollutant in the little volume of matrix.When forming passage in the base material, than the passage of minor diameter for example 200,400,500,600,700,800,900,1000,1100,1200,1300,1400,1500,1600,1700,1800,1900,2000,2100,2200,2300,2400 or the passage aisle of 2500cpsi be preferably to keep high surface.

In another embodiment, passage runs through the whole length of base material.This base material has through-flow configuration.

Perhaps, passage does not run through the whole length of base material and runs through about 50% to about 99% of base material length.This base material is considered as wall stream configuration.The remaining part of not boring can have different-thickness in the passage of wall stream base material.Fig. 8 illustrates wall-flow type base material 820 according to one embodiment of the present invention, and the not brill part 840,845 of different wall is arranged.In this embodiment, the admission passage that replaces has than other admission passage and the wideer wall thickness of passing away.But the different segment thicknesses that do not bore can any composite construction make and enter or passing away has thinner or thicker not brill part, wherein all do not bore the thickness of part can be similar substantially or dissimilar.So thin and porous of wall thickness so that waste gas 830 enter passing away from the exhaust admission passage by wall, catch pm emission.The length of boring between the inner edge 850 and 855 partly is called the zone of intersection.Do not bore in the some or all of admission passages under the thicker situation of part 840, exhaust stream 830 may leave base material 820 by the conduit wall of base material in the zone of intersection.Exhaust stream 830 may be still by thin not brill part 845.In another embodiment of the present invention, the not brill of passage part is impregnated catalyst optionally, thereby different on the amount of catalyst and the conduit wall.

This thickness that does not bore part is restricted.Increase gas flow by the surface area that increases the suitable wall of thickness.If it is too thin not bore part, may break because of extra back pressure.

Machine drilling

In case the embodiment of base material cuts out from blank and machining, just can be inserted in the boring grab and hole.Can be basically parallel to cylinder main shaft and toxic emission flow direction and in base material, bore a plurality of passages.Channel diameter is more little, and the passage that disposes in the base material can be many more.

In another embodiment, in base material, drill through.Base material is placed in the boring metal fixture.These anchor clamps can be for example a pair of big metallic walls, the base material semi-finished product are fixedly secured in place, make it to move and base material are not crushed simultaneously.Anchor clamps are bitten base material, make it to keep the stable boring that is used for.After one sidetracking of base material was intact, anchor clamps Rotate 180 degree were exactly holed at the opposite side of base material.If not Rotate 180 degree exactly, the passage that then gets out is with incomplete alignment or parallel.And the pressure of porch needs basic identical or close with the pressure in exit.Parallel for guaranteeing wall, anchor clamps must make the base material direction of why not expecting in office not be moved beyond 0.0001 inch.

The passage of base material of the present invention can prepare with the machine drilling method.In a kind of embodiment, utilize computer numerical control (" CNC ") boring, this is very common in machinery plant, and is preferable methods.CNC boring slowly many, in needing every day and produce the extensive manufacturing environment of thousands of filters, be not economically viable.CNC borehole accuracy and accuracy height.CNC boring is finished by the drill bit multipass.The every journey of CNC is bored more deeply in base material, removes fibrous material when drill bit comes out.

Drill bit can be a tungsten carbide, because of it has toughness and fragility, also can be the known similar material of those of ordinary skills.

Drill bit penetrates with the feed speed of about 10 feet per minute clocks.For preventing that the drill bit fusing from needing slow feed speed.When drill bit penetrates with the feed speed of 25 feet per minute clocks, the drill bit fusing.And because hole is very big, drill bit has the tendency of moving about or moving.But the slower head it off of penetration speed.

Preferred rotary drilling-head at a slow speed.200 rev/mins of rotary drilling-heads of Ying Yiyue.For example about at a relatively high speed 10,000 rev/mins of rotary drilling-heads may cause the drill bit fusing.With lubricator make drill bit keep cooling during the whole boring as water, alcohol or glycerine.

In case base material cutting and sand milling to final size, just cut or get out passage in base material.In this example embodiment, use the DPSSL cutting channel.Because base material is porous and permeable, base material needn't resemble the conventional filter thick.In addition, thin or less base material production cost is lower, can produce a plurality of base materials because cut a compact material, and any coating that need apply or catalytic amount reduce.

Water bores

In another embodiment, utilize water to cut (or water brill) and form passage.Water cut utilize unusual high pressure thin water jet in base material inscribe hole.But can not stop water in cutting process annotates so that stay blind hole (promptly not passing completely through the passage of base material).The physical characteristic that water is annotated makes the access portal size be limited to diameter and is not less than water notes diameter.In some embodiment, available water is annotated and is formed rectangular opening.

Pneumatic drill

Another aspect of the present invention is equipped with base material with the pneumatic drill legal system.Pneumatic drill is known in the art, can be used for base material of the present invention to prepare passage in base material.

Comb is pressed

In another embodiment, form or shaping channel with the comb platen press.Described comb is preferably the metal device of the pointed tooth of a plurality of being pressed into (for example reaming) base material.The comb that is used for reaming comprises a plurality of pointed tooths.The length and width of pointed tooth, thick and shape can change according to want channel properties, configuration and size.

In some embodiment, comb is basically perpendicular to substrate surface is pressed in the base material.In other embodiment, with comb and substrate surface is angled is pressed in the base material.Adopting comb is preferable methods, especially for forming blind vias.Should understand also can prepare suitable comb make comb by many rows and multiple row for example 4 * 4 or 16 * 16 pointed tooths form.

Usually, described comb platen press comprise repeatedly comb is pressed into substrate material repeatedly until great majority or all channel formings.This method is called stepping herein.Thereby after being pressed into, from passage, take out comb alternatively at every turn and can from passage, remove excessive host material by for example air.Preferably during stepping/reaming step, prevent the fiber assembly.The fiber assembly can cause wall to break.For controlling this characteristic, vacuum available and/or compressed air cleaning passage and bit face.

In a kind of embodiment, using is enough to discharge from conduit wall or expel the power of a certain amount of host material that comb is pressed in the base material.In a kind of preferred embodiment, apply enough power to comb and make pointed tooth in passage, extend about 0.1 inch.Other value that is fit to comprises 0.05,0.15 and 0.2.Be preferably and form or strength that shaping channel applies is enough to form or shaping channel under the situation of not damaging conduit wall substantially.Described method comprise with pointed tooth be pressed into repeatedly base material until produce the passage of the length of wanting and shape.

The shape of the shape decision passage of pointed tooth.For example, the rectangle pointed tooth on the comb is used to form the rectangular channel of rectangular channel opening.

Wedge shape pointed tooth on the comb is used to form wedgy passage.Utilize the wedge shape pointed tooth to produce the conduit wall passage parallel with square openings.As shown in Figure 17, base material 1700 contains parallel wedge shape " blind " passage 1702, does not promptly have the passage of outlet.Closed channel 1702 forces gas 1704 to pass the pore channel wall and leaves then.

Four sides pyramid pointed tooth on the comb is used to form pyramid shaped channels.These walls are parallel and opening is square basically.But access portal place wall thickness minimum connects by the straight wall in front because passage is joined somewhere.This causes surface area to reduce, thereby back pressure reduces.With four sides pyramid pointed tooth, needn't comb be isolated with shim liner.In this embodiment, with reference to Figure 16, suitable comb has the pointed tooth that comes to a point but not flush end is arranged.Certainly, the present invention includes the pointed tooth of various other shapes.

Tent shape pointed tooth on the comb is used to form the polygon passage.The surface area minimum of polygon passage.

Referring to Figure 16, the size according to the example comb 1600 of one embodiment of this invention is shown.Comb 1600 is about 6.000 inches long and 0.0308 inch wide.Comb 1600 comprises pedestal 1610, therefrom stretches out a plurality of pointed tooths 1620.Pedestal 1610 is high 0.4375 inch.A plurality of pointed tooths 1620 are 1.250 inches long and 0.0308 inch wide, 0.010 inch at interval.

In a kind of embodiment of comb platen press, passage forms with drill bit earlier, is circular.For generation has the shaping channel of parallel walls, according to one embodiment of this invention, the pointed tooth of comb makes circular channel reaming (i.e. extruding or punching press) produce shaping channel.A kind of embodiment of comb shown in Figure 15 1500.Preferably on the CNC stamping machine, carry out reaming.The impression that stays is shaping channel and access portal.The wall thickness in hole can change as mentioned above.In some embodiment, the comb platen press produces catalysis or the filtering substrate of about 4 mils of channel wall thickness to about 20 mils, preferred about 6 mils to about 10 mils.

In the comb platen press, metal combs can be placed in the box that is called anchor clamps and be installed in the CNC stamping machine and be used for reaming.In anchor clamps, comb is isolated with shim liner.Spacing between the comb is low tolerance, moves thereby require comb to be clamped in interior restriction of anchor clamps tightly during reaming.Referring to Figure 16, shim liner 1630 is as the spacer of comb 1600.The size of shim liner 1630 is wide 0.010 inch, long 6.000 inches, high 0.4375 inch.

Preferably above comb, provide at least one net to aim to keep pointed tooth.Preferred described net is aiming to distribute as required of floating.In addition, described net for different length for example about 0.5 inch to about 6.0 inches long pointed tooths be useful.Described at least one net can place along pointed tooth in any position, as unsteady, spring loaded or fixing.Described at least one net can float along pointed tooth.Described pointed tooth is not fixed on that described at least one is online, makes net adjustable on the pointed tooth but net is placed on.Described at least one net available spring loaded on pointed tooth.Spring loaded described net, base material to the pressure of net near the distance that keeps the base material edge between the pointed tooth.Described at least one net also can be fixed on the pointed tooth, in any position along pointed tooth length.

Another embodiment of the present invention relates to a kind of the have catalysis of a plurality of passages or the preparation method of filtering substrate, comprises with comb stepping on base material forming a plurality of passages.In the preferred embodiment, this method is a kind of step-by-step procedure.Be that whole passage is not to use the pointed tooth of comb to insert once formation.But the pointed tooth that inserts and take out comb with very little increment repeatedly is until obtaining the passage length of being wanted.Preferably between each stepping or every a stepping, from passage, remove the host material of expulsion.

In another embodiment, described comb platen press is to utilize machine and/or robot to form the automation process of passage.

The method for making of comb

Be used for comb of the present invention many preparation methods are arranged.Described comb can be made by the material that includes but not limited to stainless steel, tungsten or key stock.The forming method of comb comprises that laser cutting, water cut and available other forming method of those of ordinary skills is processed or utilized to electron discharge.

Available DPSSL makes comb.Also can utilize water to cut the manufacturing comb.For example, utilize the water method of cutting once to cut in a kind of embodiment and make 30 to 40 combs.

Electron discharge processing (" EDM ") is a kind of optional method of preparation comb.EDM is a kind of heat etching process, is removing conductive material by a series of reignitions between electrode and the electrically conductive workpiece in the presence of the dielectric fluid.If make the base material conduction, can on base material, use EDM similarly.EDM has at least two types: (1) percussion hammer and (2) wire.

When using the EDM percussion hammer to be die sinking, electrode/instrument be connected on the percussion hammer, percussion hammer links to each other with a utmost point (normally positive pole) of the pulse power.Workpiece links to each other with negative pole.Place work piece makes between workpiece and the electrode and has the gap then.In the gap, inject dielectric fluid.In case power-on, then the direct current of the thousands of pulses of per second or DC cross over described gap, the beginning erosion process.The spark temperature that produces can be in 14,000 to 21,000  scopes.Along with the continuation of corroding, electrode is keeping carrying out work under the constant situation of gap size.

Preferably use wire EDM manufactured comb.The wire method is used for the live metal silk that consumes as electrode, when it produces complicated otch with predetermined pattern when workpiece moves.

When wall was too thin, any burr when advancing during reaming or going out on the pointed tooth all may tear described wall.Therefore, the comb polishing should be removed any burr or the sharp edge that may hook fiber.Comb cut and polish can produce heat, this may make comb become curved.Parallel and do not break for the hole of guaranteeing to produce, preferably keep about 0.0001 inch tolerance.

The employed comb of reaming comprises a plurality of pointed tooths.The length and width of pointed tooth, thick and shape can change according to the attribute of want passage.Referring to Figure 16, the size according to the comb 1600 of one embodiment of this invention is shown.Comb 1600 is about 6.000 inches long and 0.0308 inch wide.Comb 1600 comprises pedestal 1610, therefrom stretches out a plurality of pointed tooths 1620.Pedestal 1610 is high 0.4375 inch.A plurality of pointed tooths 1620 are 1.250 inches long and 0.0308 inch wide, 0.010 inch at interval.

Laser Processing

Other method comprises solid-state laser (" the DPSSL ") boring of diode pumping; Chemical laser is CO for example ₂Electron beam (" EB ") boring; Or electrode drilling machine (" EDM "), or utilize other known method of those of ordinary skills.Can adopt any laser that is fit to cutting comb material.

Available laser drill such as DPSSL boring cutting base material.This method utilizes the laser of CAD programming to hole.The CAD program is packed in the CAM program.Described laser instrument dashes with thready pulse and cuts with oxygen or preferred nitrogen.DPSSL can about 2,000 passages of per minute the speed cutting channel.In a kind of embodiment, about 100 nanometers of channel diameter.Laser drill can adopt known technology and method to carry out, and is disclosed in 128 as US 4,686, and its instruction all is incorporated herein for reference.In a kind of embodiment, described technology utilization laser drill prepares about 0.5 inch or the passage of low depth (or length) more.

In a kind of embodiment, the passage of generation enough enters with the permission particle greatly but is enough little of to remove most of particles from waste gas stream.

In addition, in a kind of embodiment, described matrix voidage 97% this means that a large amount of spaces is used for gas and passes base material.Big like this porosity also provides additional surfaces long-pending for particle deposition.

Pulse laser

Gator series	G355-3	G532-5	G532-10
					Wavelength	355	532	1064	nm
Average output power 1)	3	5	10	W
					Pulse recurrence frequency 2)	0-15,000	0-15,000	0-15,000	Hz
Pulse energy 1)	0.3	0.5	1	mJ
					Pulse duration (FWHM) 1)	15±3	15±3	15±3	Ns
Beam diameter (l/e 2) 1)	1.0 *	1.0	0.7	mm
					Spatial model	TEM 00	TEM 00	TEM 00
M 21)	＜1.2	＜1.2	＜1.2

1) under the 10kHz repetition rate, measures;

2) 0-15,000Hz (decay power) external trigger.7500Hz to 15, the 000Hz internal trigger.0 and 15, the actual random ignition mode of external trigger is optional between the 000Hz with the peak power pattern.3) the Gator laser instrument utilizes the closed loop water system to carry out temperature control.

Preferably when using Laser Processing, described host material is substantially free of impurity such as carbon.

Molded aperture

In another embodiment, the base material of the present invention of preparation preformed channel in blank.In this embodiment, in blank, produce passage with the channel forming machine.Channel pattern is the bar that suitable size and dimension is arranged, and forms the passage of wanting when forming green compact.

Described channel pattern can use dissimilar materials.For example, described channel pattern can be very durable material, for example can tolerate the metal or the polymer of drying process temperature.In case form green compact or final blank, just take out described bar and stay passage.Described passage can further as previously described machining.

Perhaps, in other embodiments, described bar is made by the material that is exposed to suitable radiation or thermal source such as laser or can evaporate or decompose when hot.In another embodiment, described channel pattern is made by carbon or carbon derivative etc.

The specific embodiment

In some embodiment, drill through with the CNC rig, described rig by computer control to keep consistency, as hereinafter described.Described boring procedure carries out under constant shower water to prevent that dust gas carries, and this has OSHA danger, may enter the rig bearing and damages rig.

Bore the back base material and before applying any catalyst, remove or cure any water or other liquid that may exist in the hole at the baking oven inner drying alternatively.The time of curing is unimportant.Remove major part or all basically water with time enough.The weight of weighing base material just can be determined evaporation of water simply.The time of curing is mainly quickened dehydration.After filter element heated with several different time intervals, weight was stable, and then base material prepares to be used to apply any catalyst or coating.

In a kind of preferred embodiment, prepare the passage of base material earlier then with the moulding of comb platen press by boring.Because the thermal conductivity of preferred substrates is low, when hole to base material, hole and the cutting technique process in the most reflected back drill bit of heat that produces and away from base material.Therefore, drill bit may absorb some heats and expand, overheated and/or the fusing.Preferably carry out the cooling of drill bit, preferred water cools off.In another embodiment, described rig is for example operated under the 200RPM and is minimized with the heat that will produce reducing drilling speed.Certainly, other drilling speed (faster and slower) also is suitable for.In another preferred embodiment, two or four or six rigs with improved distortion and drill bit (apex point) configuration are adopted in described boring.

In addition, in a kind of preferred embodiment, through repeatedly getting out passage.For example, can prepare the passage that is about 1 inch deeply for about 0.1 inch by pierce base material at every turn until reaching final lengths.Can remove the host material that gets out in the passage between the boring.

Centre punching and locating hole

Adopt step-by-step method, bore the material that empty chopped strand got out because must remove.

In a kind of preferred embodiment, can be loaded into additional areas thereby get out part blind vias fiber in comb compression technology process darker than the plan degree of depth.The design comb enters the degree of depth of the wall stream configuration of regulation, and extra space holds remaining any loose base material in the passage.

The method products obtained therefrom

In another embodiment, the present invention relates to product by the methods described herein preparation.Particularly, the present invention relates to catalyst substrates by arbitrary specific embodiments preparation described herein.On the other hand, the present invention relates to filtering substrate by arbitrary specific embodiments preparation described herein.

Use

Discuss various embodiments of the present invention and application below.Discussing these application examples only is used to illustrate but not limits the scope of the invention.Arbitrary embodiment of above-mentioned catalyst substrates and filtering substrate all can be used in various application.

Catalytic converter

In another embodiment, the present invention relates to comprise the catalytic converter of catalyst substrates of the present invention.The occupation mode that catalytic converter of the present invention can be similar to known catalytic converter is used for engine exhaust system.Certainly, catalytic converter of the present invention has the advantage that is better than the prior art catalytic converter.Because these advantages, described catalytic converter can the out of use mode of known catalytic converter use.

Arbitrary specific embodiments of base material of the present invention all can be used in one or more concrete application examples such as catalytic converter as mentioned above.In a kind of specific embodiments, described catalytic converter comprises catalyst substrates of the present invention; Surround the bed course of described catalyst substrates; And jar, the preferable alloy jar; And also comprise wash coat alternatively.

Another aspect of the present invention relates to a kind of interior or adjacent with it catalytic converter of exhaust manifold that places engine exhaust system, and described converter comprises catalyst substrates of the present invention.This catalytic converter is called manifold catalytic converter (other term comprises manifold catalytic converter, manifold converter etc.).Manifold catalytic converter of the present invention comprises manifold catalytic converter known in the art, wherein replaces the prior art base material with catalyst substrates of the present invention.This manifold catalytic converter for example is disclosed among the US 6,605,259 and 5,692,373.

In another embodiment, the present invention relates to a kind of improved catalytic converter, described improvement comprises novel base material described herein.Arbitrary specific embodiments of described base material all can be used for described improved catalytic converter.

In another embodiment, the present invention relates to a kind of improved catalytic converter that is used to handle engine exhaust gas, it comprises base material, metal oxide wash coat and at least a catalyst that is adhered to metal oxide particle, described improvement comprises base material, and described base material comprises nSiRF-C composite and catalytic metal.

In another embodiment, the present invention relates to a kind of improved catalytic converter that is used to handle engine exhaust gas, comprise base material, metal oxide wash coat and at least a catalyst that is adhered to metal oxide particle, described improvement comprises base material, and described base material comprises nSiRF-C composite and catalytic metal.

In another embodiment, the present invention relates to a kind of improved catalytic converter that is used to handle engine exhaust gas, comprise base material, metal oxide wash coat and at least a catalyst that is adhered to metal oxide particle, described improvement comprises base material, and described base material comprises the AETB composite.

In another embodiment, the present invention relates to a kind of main catalytic converter that catalyst substrates is arranged, described catalyst substrates comprises nSiRF-C composite and catalyst.Described main catalytic converter (being sometimes referred to as underfloor catalytic converter) partly or entirely is positioned at the engine head.In a kind of embodiment, described main catalytic converter comprises catalyst substrates of the present invention, and the density of wherein said base material is about 12lb/ft ³, porosity is about 97%, its thermal expansion is low, structural intergrity is high and thermal conductivity is low.In a kind of preferred embodiment, described main catalytic converter comprises about 600cpsi, and wall thickness is the base material of about 6 mils.Main catalytic converter described in this embodiment has wall stream configuration.In a kind of preferred embodiment, described main catalytic converter has a square openings (or hole) basically is the channel shape of box-like (by the length difference of base material) substantially.In a kind of preferred embodiment, the catalyst substrates of described main catalytic converter is made with the comb platen press.In addition, in this embodiment, described catalyst substrates comprises alumina washcoat.In this embodiment, oxidation and reduction that described main catalytic converter can the catalysis pollutant, for example have can oxidize contaminants catalyst, can go back the catalyst of parent pollutant in addition.The jar of described main catalytic converter prepares with forging method.In a kind of preferred embodiment, described main catalytic converter comprises two base material unit.In some embodiment, described main catalytic converter uses separately, perhaps is used in combination with pre-catalytic converter.In a kind of preferred embodiment, described main catalytic converter comprises the expansion bed course.Described main catalytic converter can be used for all internal combustion engines.Described main catalytic converter can use with the fuel carried catalyst.In addition, the base material of described main catalytic converter can be to strengthen protection.

In some embodiment, main catalytic converter of the present invention as mentioned above also can use with one or more after-treatment systems.These after-treatment systems comprise NOx absorber, HC absorber and SCR system etc.

In addition, the embodiment that has with same or similar configuration of above-mentioned main catalytic converter and attribute can be used for film catalyst.Described film catalyst comprises the catalyst substrates that has the film configuration as mentioned above.

In another embodiment, the present invention relates to a kind of front end catalytic converter that catalyst substrates is arranged, described catalyst substrates comprises nSiRF-C composite and catalyst.Described front end catalytic converter partly or entirely is positioned at the engine head.In a kind of embodiment, described front end catalytic converter comprises catalyst substrates of the present invention, and the density of wherein said base material is about 12lb/ft ³, porosity is about 97%, its thermal expansion is low, structural intergrity is high and thermal conductivity is low.In a kind of preferred embodiment, described front end catalytic converter comprises about 600cpsi, and wall thickness is the base material of about 6 mils.Front end catalytic converter described in this embodiment has wall stream configuration.In a kind of preferred embodiment, described front end catalytic converter has a square openings (or hole) basically is pyramidal channel shape substantially.In a kind of preferred embodiment, the catalyst substrates of described front end catalytic converter is made with the comb platen press.In this embodiment, oxidation and reduction that described front end catalytic converter can the catalysis pollutant, for example have can oxidize contaminants catalyst, can go back the catalyst of parent pollutant in addition.In some embodiment, described front end catalytic converter uses separately, perhaps is used in combination with pre-catalytic converter.In a kind of preferred embodiment, described front end catalytic converter comprises the mixing bed course.Described front end catalytic converter can be used for all internal combustion engines.Described front end catalytic converter can use with the fuel carried catalyst.

One or more front end catalytic converters can use with same engine.Use front end catalytic converter of the present invention to also have following one or more advantages: the weight saving of gas extraction system under the floor; The filtration of the exhaust gas particle thing that has increased otherwise will absorb by intercooler, thus the life-span of intercooler improve; Do not need bed course; Click in the hot baffle reduces; The silencer size reduces; Improved burnouting of particle; In some embodiment, under the situation of a front end catalytic converter failure, still available other running front end catalytic converter for example on 4 Cylinder engines in addition three handle waste gas effectively.The front end catalytic converter is useful to ship, ship, motorcycle, small-sized portable engine, the fallen leaves machine that purges with relevant engine and other application of preferred non-exposure catalytic converter.

In another embodiment, catalytic converter of the present invention can place between front end and the exhaust manifold, as shown in Figure 43.In this embodiment, catalytic converter partly places between engine head and the exhaust manifold.The advantage that is better than conventional system is described converter very near the combustion chamber, thereby raises the efficiency.For example, this embodiment can be installed in these catalytic converters Ford 4.6 and go up, and is fit to its all engines.This means that again it can be installed in all other products such as Lincoln product that FordExplorer, Mustang, Crown Victoria, Econoline, 150/250/350pickup, Expedition and Ford install engine.Also described catalytic converter can be installed in some embodiment and use its different automobile types year for many years.A kind of like this 4.6 foundry goods only just can be used for millions of vehicles in the U.S..It also is friendly for the adding of lambda sensor.

In another embodiment, the present invention relates to a kind of back catalytic converter that catalyst substrates is arranged, described catalyst substrates comprises nSiRF-C composite and catalyst.In another embodiment, catalytic converter of the present invention is the back catalytic converter.Described back catalytic converter is positioned at after the main catalytic converter.In a kind of embodiment, described back catalytic converter comprises catalyst substrates of the present invention, and the density of wherein said base material is about 12lb/ft ³, porosity is about 97%, its thermal expansion is low, structural intergrity is high and thermal conductivity is low.In a kind of preferred embodiment, described back catalytic converter comprises about 600cpsi, and wall thickness is the base material of about 6 mils.The catalytic converter of back described in this embodiment has wall stream configuration.In a kind of preferred embodiment, the catalyst substrates of described back catalytic converter is made with the comb platen press.In a kind of preferred embodiment, described back catalytic converter has difform access opening, comprises triangle, square and hexagon.Equally, channel shape can change.In this embodiment, oxidation and reduction that described back catalytic converter can the catalysis pollutant, for example have can oxidize contaminants catalyst, can go back the catalyst of parent pollutant in addition.In some embodiment, described back catalytic converter uses separately, perhaps is used in combination with pre-catalytic converter.In a kind of preferred embodiment, described back catalytic converter comprises unexpansive bed course.Described back catalytic converter can be used for all internal combustion engines.In another embodiment, described back catalytic converter does not use with the fuel carried catalyst.Usually, the back catalytic converter of this embodiment places near the standard silencer position, but also can in other position.In a kind of optional embodiment, described back catalytic converter is incorporated in the silencer.This embodiment can comprise: a) base material itself plays the silencer effect and replaces silencer, or b) base material places and makes it to incorporate into silencer in the typical metal muffler assembly.

In another embodiment, the present invention relates to a kind of diesel oxidation catalyst (DOC), wherein the base material of DOC is a catalyst substrates described herein.In a kind of preferred embodiment, the base material of DOC of the present invention is AEBT or OCBT, preferred AEBT-10, AEBT-12, AEBT-16 or OCBT-10.Described DOC embodiment has and is selected from palladium, platinum, rhodium, their mixture, and their catalyst of derivative.

Other embodiment that is fit to comprises the catalysis DPF that contains catalyst substrates of the present invention, and preferred described base material comprises AETB material such as AEBT-12, also comprises catalyst.

Particulate filter (DPF, DPT)

In another embodiment, the present invention relates to comprise the particulate filter of catalyst substrates of the present invention.Particulate filter of the present invention can be similar to and use the mode of known catalytic converter to be used for engine exhaust system.Certainly, particulate filter of the present invention has the advantage that is better than the prior art catalytic converter.Because these advantages, described catalytic converter can the out of use mode of known catalytic converter use.

In another embodiment, the present invention relates to a kind of improved particulate filter, described improvement comprises novel base material described herein.Can use arbitrary specific embodiments of described base material in the described improved particulate filter.

In another embodiment, the present invention relates to a kind of improved particulate filter that is used to handle engine exhaust gas that comprises filtering substrate, described improvement comprises base material, and described base material comprises the nSiRF-C composite, and a plurality of passages that stretch into and run through described base material are alternatively arranged.The configuration of passage can change, and provides as the front.

In another embodiment, the present invention relates to a kind of improved particulate filter that is used to handle engine exhaust gas that comprises filtering substrate, described improvement comprises that described base material comprises the nSiRF-C composite, described composite is had an appointment and 100 is run through the passage of described base material to about 1000, preferred about 600 parts, and wherein said base material has wall stream configuration.

In another embodiment, the present invention relates to a kind of improved particulate filter that is used to handle engine exhaust gas, comprise base material and metal oxide wash coat, described improvement comprises base material, and described base material comprises AETB.

In another embodiment, the present invention relates to a kind of diesel particulate filter (DPF) that filtering substrate is arranged, described filtering substrate comprises nSiRF-C composite as mentioned above.Constructing described filtering substrate makes it be applicable to DPF.Described DPF partly or entirely is positioned at the engine head.In a kind of embodiment, described DPF comprises filtering substrate of the present invention, and the density of wherein said base material is about 12lb/ft ³, porosity is about 97%, its thermal expansion is low, structural intergrity is high and thermal conductivity is low.In a kind of preferred embodiment, described main catalytic converter comprises about 600cpsi, and wall thickness is the base material of about 6 mils.Main catalytic converter described in this embodiment has wall stream configuration.In a kind of preferred embodiment, described main catalytic converter has a square openings (or hole) basically is the channel shape of box-like (by the length difference of base material) substantially.In a kind of preferred embodiment, the catalyst substrates of described main catalytic converter is made with the comb platen press.In addition, in this embodiment, described catalyst substrates comprises alumina washcoat.In this embodiment, oxidation and reduction that described main catalytic converter can the catalysis pollutant, for example have can oxidize contaminants catalyst, can go back the catalyst of parent pollutant in addition.The jar of described main catalytic converter prepares with forging method.In a kind of preferred embodiment, described main catalytic converter comprises two base material unit.In some embodiment, described main catalytic converter uses separately, perhaps is used in combination with pre-catalytic converter.In a kind of preferred embodiment, described main catalytic converter comprises the expansion bed course.Described main catalytic converter can be used for all internal combustion engines.Described main catalytic converter can use with the fuel carried catalyst.In addition, the base material of described main catalytic converter can be to strengthen protection.Protective finish can be coated on the inboard or the outer surface of base material.

Canned type

Catalytic converter of the present invention has a jar.Described jar can prepare by means known in the art.And the available material known in the art of jar of catalytic converter of the present invention or particulate filter for example steel is made.

In a kind of preferred embodiment, catalytic converter of the present invention has outlet, and outlet can link to each other with the tailpipe that is purchased vehicle.The about 2.5 or 3 inches tailpipe of preferred described catalytic converter fit diameter.

For example, the jar that is fit to comprises the jar by following either party's manufactured: clam shell, tie, footwear box, filling and forging.Above-mentioned canning method utilizes two kinds of different clearance control mechanism: the fixing canned power in (1) fixed interval (FI) and (2).From welding method, these methods produce the converter that one or two seam is arranged.These classification are shown in following table (Rajadurai 1999).

	The fixed interval (FI)	Bed knife
			Single joint	Filling, forging	Tie
Double joint	Clam shell	The footwear box

With bed knife seal this jar by the dimensional tolerance of eliminating base material, jar and bed course itself influence provide more accurate between gap density control.Jar is closed to the fixed interval (FI) advantage is to produce the fixing converter of final size, this makes the converter design simplification, mainly is aspect the welding of cone and final jar.

The usually preferred single joint design of the circular or oval converter that aspect ratio is low can provide uniform gap Density Distribution.It is lower that the shell of single joint also has bigger manufacturing flexibility and a processing charges.The oval converter that aspect ratio is high needs the double joint design usually.In the case, in shell, stamp out ribs prevent its distortion and the gained gap inhomogeneous.The pressing production of double joint shell, processing charges is very high and need the output height.

Clam shell

In a kind of embodiment, catalytic converter of the present invention comprises the jar made from the clam shell technology.In another embodiment, described particulate filter comprises the jar made from the clam shell technology.In North America, clam shell is the most general design traditionally of converter under the floor in passenger vehicle and the light truck.The structure of the catalytic converter of clamshell style shown in Fig. 6.The ceramic catalytic base material is wrapped in the bed course and places the bottom of shell.Another symmetric part with shell is placed on the top then, forces together, and welds.

Walk around base material with slip feather designs fix bed course to avoid waste gas.The above converter also comprises the end sealing.Described sealing is used herein to the protection bed course and avoids air impingement and erosion, but not prevents to leak.Use the converter of bed course not have the end sealing mostly.As long as install to replace bed course, just need the end sealing, at least in the inlet front of base material with woven wire.

The clamshell style converter is equipped with outer hot baffle usually.Also developed the internal insulation design, clam shell pressed part inboard is lined with extra heat insulation layer.

Support ring or dark bag that older catalytic converter design is included in the clam shell pressed part prevent that base material from moving axially in jar.In the converter of suitably design, adopt the high expansion bed course of support pressure, do not need this measure.There is the base material of many automotive converters not have axial support, still shows very high durability.But bigger and heavier base material or may need axial support when using the unexpansive bed course of low support pressure.Another consideration is the erosion of bed course.The profile of converter shell or end tapered should design the direct bump of avoiding hot waste gas with the protection bed course like this.Some converter manufacturer improves its corrosion resistance with the bed course edge that the chemical substance dipping is exposed to gas.The high support pressure of modern converter also makes the corrosion resistance of bed course improve.

During using, use by many automobiles two integrally-built converters.Because the manufacturing of overall structure length limits or merges the catalyst of different size in a converter, can use two or more overall structures.In most two integrally-built converters, base material is spaced apart separately, keeps at interval by form the separation bag in the clam shell pressed part.In some design, with the interval between metal or the ceramic ring maintenance base material.Not having butt joint monoblock at interval to arrange therebetween also can.The commercial converter of some petrol engine (Kuisell, R.C., 1996, " Butting Monoliths in CatalyticConverters, " SAE 960555) middle employing butt joint design, it is littler than interval design pressure drop.

The geometry of converter shell must provide desired bed course compression.The clam shell profile comprises that the punching press ribs is to provide desired stiffness and uniform pressure distribution.This is particularly important to flat oval catalyst substrate.Should note not existing the excessive zone of pressure that may cause base material or bed course to damage during the design rib.The clam shell method is to the size tolerance requirements height of overall structure and clam shell pressed part.The bed course compression continued to the sealing of half shell during clamshell style was canned, produced certain clearance thickness.Gap thickness depends on the size of overall structure and shell.Thereby any variation of overall structure size all causes bed course density to change and consequential canned pressure change, and canned pressure change may cause the converter endurance issues.

Tie is the most frequently used method, and it can directly control the fixation pressure in the canned process.Because tie is insensitive to the difference in size that may exist in the base material overall structure, so can produce the firmest catalytic converter.In fact, the tie method is limited to circle or approaching circular catalyst substrate cross section.It is very limited to the applicability of the ellipse that uses under the floor or flat elliptic automotive converters.Tie is popular in European car manufacturer again, but along with automotive converters is displaced downwardly to the position that is close to engine from the floor, it becomes more general in North America.Tie also is fit to the heavy duty diesel engine larger diameter catalytic converter.

In the tie technology, earlier base material is wrapped in the slip feather shape bed course.To wrap up good overall structure then is placed in the jar that vertically splits.This jar is rolling with rectangular metal plate.Usually the rectangle part below the overlap is splayed.In some design, jar overlap form outstanding antelabium by extra punching operation and provide the space for the jar limit below the overlap.This design prevents that the inner edge of jar from cutting in the bed course or the generation local pressure accumulates, and this may damage canned part, when especially use approaches bed course.To there be parcel to be placed in the taping machine for integrally-built jar then, apply the power of control to assembly.When pressurized still, jar is carried out spot welding, in taping machine, take out, stitch weldering.Sometimes carry out push out test as quality assurance measure.In the special test device, measure and apply integrally-built axial displacement due to the control.At last, converter collector or end cone and flange and/or port are welded on the converter body in independent operation.The welding quality that can test final assembly with air pressurized when immersing in the water.

Taping machine comprises the steel band ring to the canned parts application of force.One end of ring firmly is connected with the machine rigidity and the other end is drawn by pneumatic or liquid braking device.Apply vibration closing force is minimized and guarantee that pressure distribution is more even during some machine is inherent canned.

Can determine to reach the canned power of target constant density actual needs by a series of tests for given bed course.Several converters are used different closing force closures.Should select to produce the canned power of the bed course density of wanting.Because bed course pressure is lax, taping machine produces repeatably that closing speed and temporal mode are important.Reach after the target closed power, described machine should make jar remain on constant position, allow to carry out spot welding, and be not with constant power.When the bed course relaxation pressure, apply constant power and will cause the bed course excess compression to jar.

Footwear box technology adopts shell divided into two parts, is similar to the clam shell method.But this shell is closed under bed knife, the edge of one of half shell and the overlapping edges of second half shell.Thereby the footwear box has the advantage that has strong packing of tie aspect insensitive in the dimensional tolerance of itself and base material.

Can be on the footwear box punching press ribs.Thereby this technology can be used for canned flat elliptic base material under the unaccommodated situation of tie.

Filling

In the filling technology, the overall structure that bed course is wrapped up pushes in the circle tube tank.This jar is made by one section pipe usually but also can be rolling and be welded by metallic plate.Non-cylindrical (for example trapezoidal) is also passable.This method can be used for the converter and the big converter of heavy-duty engine of station wagon.Promote described overall structure steadily to insert (Li with the filling cone, F.Z., 2000, " TheAssembly Deformation and Pressure of Stuffed Catalytic ConverterAccounting for the Hysteresis Behavior of Pressure vs.Density Curve ofthe Intumescent Mat ", SAE 2000-01-0223).After described operation is finished, the end cone is welded on the cylinder two ends finishes canister assembly.

Though converter outward appearance of stopping up and tie component class are seemingly, actual base material fixed mechanism is identical with clamshell designs.Especially the bed course fixation pressure depends on shell and integrally-built physical dimension.Require the repeatability of substrate diameter high when therefore, adopting choked technique.

Corning (Eisenstock, G., et al., 2002, " Evaluation of SoftMountTechnology for Use in Packaging Ultra Thinwall Ceramic Substrates ", SAE2002-01-1097) modification of the described filling technology of proposition is called soft packing technique.Thereby purpose be the maximum pressure of bed course is minimized can the lower ultra-thin-wall base material of canned intensity.Key is to adopt the convergent cylindrical tool that is called axle that is placed on the base material front to respond to the maximum pressure of bed course during insertion.

In the described soft installation method, earlier bed course is inserted in the jar, jar is fixed on the flange in this process.Then, the jar (being that axle is positioned at above the base material) on axle and base material with the bed course lining pushes away downwards.Inwardly cut sth. askew and be easy to fill in the jar-bed course assembly in the axle end.Axle is pushed a bed course through out-of-date facing to jar.When base material substitutes the axle inflow location in jar, be not subjected to extruding the required instantaneous peak load of bed course.

Forge

In the converter that forges, after the base material of bed course parcel has inserted, the converter shell is machined to required diameter.Forging is newer packing technique, finishes in being applicable to the Full Automatic CNC control appliance that mass-produced passenger vehicle is used.The converter that forges can be made by one section pipe and end cone thereof, and they obtain with rotoforming in same production equipment.

Clearance control mechanism can classify as permanent gap thickness, and is identical with the situation of filling, but that CNC control production line can calculate substrate diameter automatically is poor.Forge converter and must make the diameter of the aimed dia that is slightly smaller than final products earlier, after processing, allow shell " rebound ".This is a shortcoming of this method, may cause canned during the too high and base material of maximum pressure damage.

The catalytic converter collector provides transition between inlet tube and outlet and base material cross section.Most of converter collectors are taper or the funnel that axial flow is arranged.Other design is as truncation collector (Wendland, D.W., et al., 1992, " Effect of Header Truncation on MonolithConverter Emission Control Performance ", SAE 922340) or have the collector of tangential gas access also can use but be of little use.The effect of inlet header is to make the inlet flow diffusion, promptly falls low gas velocity and improve its static pressure under the as far as possible little situation of pitot loss.In fact, total collector loss can account for 10% to 50% of total converter pressure drop, depends on geometry and flox condition.Can provide the converter inlet header of more even flow distribution with these minimise loss of pressure by design.Also there is the interior flow distribution of catalytic converter evenly to improve the idea of its discharge performance and/or durability.In one embodiment of this invention, the have an appointment collector of 30% angle of catalytic converter or particulate filter.

Bed course

Catalytic converter of the present invention or particulate filter also comprise bed course alternatively.The described arbitrary embodiment in front or back can comprise bed course.In some embodiment, the present invention also comprises bed course (or pad or cotton-wool).For example, in a kind of embodiment, catalytic converter of the present invention comprises catalyst substrates, bed course and jar as mentioned above.Be applicable to that bed course of the present invention is known in the art.

Bed course can be selected according to many attributes described herein and known in the art in some embodiment.The preferred catalytic converter of design like this jar is to provide given catalyst substrates and the required fixation pressure of given bed course.Bed course is increased by the fixation pressure exponential form that its initial bulk density is compressed to bed course during the final goal density.It is loose that fixation pressure shows viscoplasticity, and the highest initial pressure that occurs when promptly canned is in that initial several seconds or several minutes are significantly reduced (Myers 2000) because of the bed course fiber rearranges thereafter.The expansion bed course because of fixation pressure due to loose be lost in initial maximum flexibility pressure 30 and 60% between change.

Because bed course is loose, and the pressure loss in using afterwards, fixation pressure is not the parameter that makes things convenient for that is used for canned technological standards.Be used for described purpose and use constant density-Chang to be called gap bulk density (GBD) usually.The definite density that is used for given application should be consulted with the bed course manufacturer, is referred to as basic weight.Weight/area g/m ²Or kg/m ²Expression (, use " mass/area " strictly speaking and replace idiom " weight/area ") because these are quality but not unit of weight.Available bed course weight/area 1050 to 6200g/m ²In the scope, not compressed thickness 1.5 and 10mm between.Automotive converters is used 3000-4000g/m usually ²The expansion bed course.More overcritical application or big converter are recommended to use higher bed course weight, as 6200g/m ²(6.2kg/m ²).

Another critical nature of catalytic converter fixed bolster is its weight/area ratio, is also referred to as basic weight sometimes.Weight/area g/m ²Or kg/m ²Expression (, use " mass/area " strictly speaking and replace idiom " weight/area ") because these are quality but not unit of weight.Available bed course weight/area 1050 to 6200g/m ²In the scope, not compressed thickness 1.5 and 10mm between.Automotive converters is used 3000-4000g/m usually ²The expansion bed course.More overcritical application or big converter are recommended to use higher bed course weight, as 6200g/m ²(6.2kg/m ²).

Wrapped pad may be subjected to corroding due to the hot waste gas bump.Erosion resisting is the key character of bed course.Erosion resisting depends on the bulk density in gap strongly.(Rajadurai, S. etc., 1999. " Single Seam Stuffed Converter Design for Thinwall Substrates ", SAE1999-01-3628).

Many other attributes of fixed bolster through regulation and/or test, can obtain from bed course manufactory.The example of these attributes comprises thermal conductivity, gas tightness and coefficient of friction etc.

In the process of designs fix system, to consider following item in certain embodiments:

Fixation pressure: suppose that fixed bolster is the only resource (being that converter is not held envelope or support ring) that connects base material and shell, utilizes the frictional force combination of radial pressure and mat surface that mechanical attachment is provided.Fixation pressure is to make the required minimum pressure of base material fix in position.

Maximum flexibility pressure.As previously described, bed course has the character as viscoelastic solid, produces the peak fixation pressure in the initial compression process, loosely gradually then reaches residual fixation pressure.In thin-walled substrates, described maximum pressure may cause the catalyst core to damage in packaging process.Also must consider this transient behavior of bed course during the design canning method, transient behavior relies on constant force, and is relative with permanent gap size, for example the tie method.

Temperature characterisitic.For the expansion bed course, bed course pressure depends on the temperature that is enough to activate vermiculite.The vermiculite activation needs at least 500 ℃ inlet temperature; May the higher inlet temperature of needs according to concrete intrasystem heat transfer condition.In gasoline is used, the bed course on the car is activated at engine running.May need in the diesel fuel applications catalytic converter is carried out oven, and EGT may never reach enough high levels in the diesel fuel applications between the normal vehicle on-stream period.Expanding vermiculite is that part is reversible, causes bed course to expand when temperature raises and contraction when converter cools off.This character of vermiculite produces very high fixation pressure more than the counteracting that the converter shell is expanded under higher temperature.On the contrary, unexpansive pad shows in described temperature range near constant fixation pressure.Along with temperature rising pressure reduces a little, be attributable to due to the thermal expansion of converter shell the gap and expand.Be higher than under 500 ℃ the temperature, expansion block provides the fixation pressure higher than unexpansive pad.But it is, in fact recently much lower from the fixation pressure of unexpansive pad from the fixation pressure of expansion block being lower than under 500 ℃ the temperature.Thereby it is preferred immobilization material that unexpansive pad remains in many diesel fuel applications below 500 ℃ in the converter inlet temperature.The expansion block that vermiculite content is low is created in the fixation pressure between conventional expansion block and the unexpansive pad.Mixed mat shows the stress level that is similar to unexpansive pad, but they at high temperature keep certain supercharging, offsets the gap and expands.

Expand in the gap.When converter is exposed to high temperature,, the coefficient of thermal expansion differences between base material and the shell increases because of causing gap thickness.The thermal expansion in gap may be the important source of fixation pressure loss.Be even more important in the application intermediate gap expansion of using unexpansive pad, because can not offset by expanding vermiculite.As design criteria, expanding in the gap to remain on (Olson, J.R., 2004, " Diesel Emission Control Devices-Design Factors AffectingMounting Mat Selection, " SAE 2004-01-1420) below 10%.

Expand and depend on following design factor in the gap:

Substrate diameter: base material is big more, causes the gap expansion rate high more.Thereby expand and may be still problem in large diesel engine used in the gap, although the converter temperature is lower.

Gap thickness: the gap is thick more, and it is more little to cause the gap to be expanded.

The shell temperature: the gap of the high more generation of temperature is expanded big more.

Shell material CTE: the higher steel of thermal coefficient of expansion produces higher gap and expands.Thereby, use ferrite (relative) easier grade of steel control gap to expand with austenite.

Bed course is aging.In case converter comes into operation, expansion block expands, and causes fixation pressure to increase.Many other aging actions are to cause the fixation pressure reason of irreversible loss gradually, as following factor: thermal cycle; Vibration acceleration and other mechanical factor; Bed course is soaked by water (condensate liquid, car washing liquid); Organic bond burnouts during with bed course heating earlier.

The pluses and minuses of present bed course

Conventional applications exploiting expands and unexpansive fiber mat is fixed on honeycomb substrates in the tube, as cited among European patent application EP 0884459 (Locker) and the European patent specification EP0912820 (Hwang).According to a kind of conventional system, fiber mat only allows bigger catalyst element to be fixed in the tube.

Expansion block

Expansion block is the exploitation of gasoline converter at first.To earlier 1990s, they become all internal combustion engine use and comprise ceramic blanket type the most frequently used in the use for diesel engine catalytic converter.Expansion block has the character of part reversible expansion when being exposed to high temperature.The thermal expansion curve of these pads can derive from some manufacturers, comprises 3M and Unifrax.After the expansion, they improve the fixation pressure of base material, form fixed system very reliably.Because of its temperature expansion characteristic, in fact expansion block can at high temperature improve its fixation pressure, offsets fixation pressure loss due to the thermal expansion of outer steel shell.

Expansion block is made by the alumina silica ceramic fibre and is contained vermiculite, and vermiculite makes it thermal expansion.Have 30-50% alumina silica fiber, 40-60% vermiculite and 4-9% organic bond (being generally acrylic latex) the typical composition.After converter assembles, must make temperature that bed course is exposed to about 500 ℃ of grades to realize initial bubble, this finishes on vehicle in the initial a few hours of engine running usually.At high temperature organic bed course adhesive of Fen Xieing is the reason of emitting distinctive smell when causing bed course to heat at first.

The vermiculite component limits the maximum allowable operating temperature (M.A.O.T.) of expansion block low relatively.Lose its fixation pressure significantly at about 750 ℃ temperature bed course.This temperature is normally defined average bed course temperature.Thereby if the heat loss outside the converter shell causes the bed course both sides to have thermograde, then bed course can use under higher EGT.The purposes of expansion bed course is restricted in the hot isothermal that heat loss does not take place by the conversion wall is used.This situation comprises the catalyst that is installed in the silencer, for example is used for motorcycle.

Vermiculite constituent content height also is the reason that causes fixation pressure high, especially under higher EGT.Found from the pressure of expansion block excessively for the ultra-thin-wall base material, caused these parts to damage.Use for these, bed course manufacturer has proposed to reduce the expansion block (being sometimes referred to as " senior " or " second generation " expansion block) of vermiculite content, and the fixation pressure lower than conventional design is provided.

Unexpansive pad

Unexpansive pad does not contain vermiculite.Thereby they can provide about 1250 ℃ higher temperature restriction.The key component of unexpansive pad is an alumina fibre, adds organic bond.In certain embodiments of the present invention, described catalytic converter or particulate filter comprise base material described herein and have the unexpansive pad possibility of fibrous material better.

Substrate support relies on built-in compression or fiber " spring ", and constant fixation pressure is provided in the serviceability temperature scope.Because, observing effective converter fixation pressure with temperature expansion under higher temperature, the converter shell descends.Thereby the fixed catalyst catalyst substrate is the most firm at low temperatures for unexpansive pad (opposite fully with the vermiculite pad).Along with temperature raises, the bed knife of base material reduces in the converter.

Unexpansive pad not only can be used for tolerating the high temperature application (thin-walled substrates) of high fixation pressure, and can be used for the low temperature conversion device, as is used for those converters of Diesel engine.Because they do not rely on expanding vermiculite, do not need oven in low temperature diesel engine converter.

Mix bed course

Improved catalytic converter of the present invention or particulate filter also can comprise the mixing bed course.This pad is known in the art.In a kind of embodiment, mixed mat contains two-layer design: one deck expansion block is on the unexpansive pad of one deck.Its attribute and performance are also in the centre, and be better than the low temperature fixation pressure of expansion block, but higher than the high temperature pressure of unexpansive pad.In a kind of preferred embodiment, improvement diesel particulate filter of the present invention comprises mixed mat, is used for light and heavy-duty applications.

Woven wire

The stainless steel cloth of available braiding replaces bed course to pack the ceramic catalyst base material.The fixation pressure characteristic that it has been generally acknowledged that woven wire is good not as bed course, but still can use (traditionally, Ford uses woven wire always) in some catalytic converter.Woven wire needs the end envelope to walk around base material to prevent gas all the time.

Auxiliary heating source

As the disclosed example embodiment of another configuration or front, described filter element should be included in and apply a series of electrically heated rods that add after the catalyst in the base material.Described heating element heater preferably applies after catalyst to prevent that described solidification process infringement is any and electrically contacts.In a kind of embodiment, heating element heater or rod are placed on and the position of every limit at a distance of about 1/4 inch or any requirement distance.In some embodiment, also can adopt woven wire configuration or other heating element heater described herein, place and during forming the fiber base, install perpendicular to airflow direction.Electrically contact with Nextel fabric or similar material protection.Before engine start, start heating element heater as preheater, and keep running (partly or entirely running) to surpass the temperature that auxiliary heating element reaches until EGT.

The auxiliary heating source that use is applied on the filter base makes it more effective applicable to improving the temperature in the filter base and/or extra heat evenly being distributed in whole filter base.Auxiliary heating source can contain stratie.Described heating element heater can have bar-shaped configuration, can or insert in sol-gel process after filter base forms.Filter base can have one or more electrical heating elements and described heating element heater can be simultaneously, heating independently, with circulation, form pattern or random fashion is arranged.Heating element heater can be the woven wire configuration, and this element can insert during filter base forms or afterwards.Described filter can use monometallic silk screen or multiple wire net heating element heater, and these heating element heaters can heat simultaneously or independently.In addition, the woven wire heating element heater can circulate, form pattern or random fashion arrangement heating.Described heating element heater also can adopt rod, spiral or helical configuration, inserts during forming or afterwards.Filter base can contain one or more spirals or scroll heating element heater, and described element heats simultaneously or independently, comprises adopting circulating, form pattern or random fashion arrangement.At last, filter base can contain the combination of any heating element heater noted earlier.

Except that above-mentioned stratie, auxiliary heating source also can adopt the heating element heater of infrared or heating using microwave.Various heating sources can be implemented or can be used as the external heat element to be used for the hot filtration apparatus substrate within filter base itself.Various heating sources can independently use or be used in combination with any other heating element heater or heating source.

The normal impingement that the protection filter base is avoided running in the vehicle transport in the enough durable shell of packing into of described filter base.This shell can comprise common metal shell such as stainless steel, steel or other metal alloy.Described material also can be nonmetal, comprises the ceramic base shell.Filter base can be encapsulated in insulating materials or the cotton-wool before being encapsulated into shell.The present invention also can comprise hot baffle.

The import of filter base and outlet can scribble oxidation catalyst.This catalyst can make radiative process faster, causes on the described overall system handling waste gas with the time of much shorter.Described catalyst can be a noble metal catalyst, comprises platinum, palladium or rhodium base catalyst and other catalyst.Described catalyst can directly be applied to the filter base surface.Described catalyst can be sprayed on the filter base, make filter base immerse in the solution or catalyst is injected filter base itself applies catalyst.Use oxidation catalyst will impel particle more lighting under the low temperature.In addition, catalyst also can be used as the supplemental heater in the filter base.

The waste gas filter system can be integrated with engine exhaust passage, comprises in the exhaust manifold that is integrated in engine itself.Engine is left in exhaust because filter base heat-resisting and vibration like this can place the position of next-door neighbour's engine exhaust port.The unique ability that filter base can tolerate high heat and vibration stress makes layout of the present invention and engine more much closer.Place to provide nearby and be better than to tolerate the traditional waste gas filter of high like this heat or vibration stress or the advantage of catalytic converter.

Though at length and in conjunction with its specific embodiments invention has been described, under the situation that does not deviate from its spirit and scope, can carry out various changes therein and revise apparent to those skilled in the art.Therefore, the present invention is intended to contain modification of the present invention and change, as long as they are in appended claims and equivalent scope thereof.

The specific embodiments of catalytic converter

Further specify catalytic converter of the present invention and particulate filter by following non-limiting specific embodiments.Many specific embodiments illustrations described herein but needn't limit the scope of the invention.Catalytic converter of the present invention can use on many engines and vehicle.Therefore, in a kind of embodiment, catalytic converter of the present invention is adapted at using on vehicle that following arbitrary company produces or the engine: Daimler-Chrysler; Chrysler; Dodge; Eagle; Jeep; Plymouth; General Motors; AM General (e.g., HUMMERs); Buick; Cadillac; Chevrolet; Geo; GMC; Hummer; LaSaIIe; Oldsmobile; Pontiac; Saturn; Ford; Continental; Lincoln; Mercury; Ace Motor Corp; American Motors; Avanti BMW; Daimler-Chrysler; Fiat; Ford; GAZ; General Motors; Honda; Mitsubishi; Renault; Peugeot; Toyota; With Volkswagen Group.Other comprises Holden; Lightburn; Hartnett; AlphaSports; Finch; Amuza; Australian Kitcar, FPV; Bavariacars; Birchfield; G-Force; Bomac; Bullet; Homebush; Carbontech; HSV; Classic Glass; Kraftwerkz; Classic Revival; Cobra Craft; Piper; Daktari; PRB; Daytona; Python; Deuce Customs; RCM; Devaux; RMC; DRB; Roaring Forties; Elfin; Robnell; Evans; Austro-Daimler; OAF; Puch; Steyr; Steyr-Daimler-Puch; FN; Germain; Miesse; Minerva; Nagant; Vivinus; Gurgel; Puma; A-E; AC; Allard; Alvis; Ariel; ArmstrongSiddeley; Ashley; Aston Martin; Austin; Austin-Healey; Bentley; Berkeley; Bond; Bristol; BSA; Caterham; Clan; Daimler; Dellow; De Lorean; Elva; F-L; Fairthorpe; Ford; Frazer Nash; Gilbern; Ginetta; Gordon-Keeble; Hillman; Humber; Jaguar; James and Browne; Jensen; Jowett; Lagonda; Lanchester; Land Rover; Lea-Francis; Lister; Locost; Lotus; M-R; Marcos; McLaren; MG; Morgan; Morris; Mini; Ogle; Panther; Peerless/Warwick; Piper; Range Rover; Reeliant; Riley; Rochdale; Rolls-Royce; Rover; S-W; Singer; Standard; Sterling; Sunbeam; Swallow; Talbot; Tornado; Trident; Triumph; Turner; TVR; Vanden Plas; Vauxhall; Wolseley; Bricklin; McLaughlin; Aero; Jawa; Laurin ﹠amp; Klement; Praga; Skoda; Tatra; Walter; Kewet; Elcat; Valmet; RaceAbout; Amilcar; Alpine, aka.Alpine-Renault; Bonnet; Bugatti; CD; CG; Citroen; DB; De Dion-Bouton; Delage; Delahaye; Delaunay-Belleville; Facel Vega; Gordini; Hispano-Suiza; Hotchkiss; Peugeot; Renault; Rosengart; Simca; Sizaire-Naudin; Talbot; Tracta; Venturi; Voisin; A-G; Amphicar; Audi; Auto-Union; BMW; Fendt; Glas; Goggomobil; H-P; Heinkel (Heinkel Trojan); Horch; Kasbohrer-Setra; Kleinschnittger; MAN; Magirus; Maybach; Mercedes-Benz; Merkur; Messerschmitt; Neoplan; NSU; Opel; Porsche; S-W; Smart; Stoewer; Titan; Trabant; Volkswagen (VW); Wartburg; Wanderer; Thomond; Bajaj Tempo; Hindustan; Mahindra; Maruti; Premier; Reva; San Storm; Sipani; Tata; Abarth; Alfa Romeo; Autobianchi; Bugatti Automobili SpA; De Tomaso; Dino; Ferrari; Fiat; Iso; Innocenti; Isotta Fraschini; Itala; Lamborghini; Lancia; Maserati; OM; Piaggio; Qvale; Vespa; Zust; Daihatsu; Honda (alsoAcura); Isuzu; Mazda; Mitsubishi; Mitsuoka; Nissan aka.Datsun (alsoInfiniti); Subaru; Suzuki; Toyota (also Lexus); Proton; ACE; AMI; AMM; Bufori; Inokom; Naza; Perodua; Swedish Assembly; TanChong; TD 2000; Donkervoort; Spyker; DAF; Pyonghwa; Tokchon; Kewet; Think aka.Pivco; Troll; Syrena; UMM; Aro; Dacia; Marta; Oltcit; Volga; Moskvitch; GM Daewoo Motors; Hyundai MotorCompany; Kia Motors; Renault Samsung Motors; SsangYong MotorCompany; Nilsson; Nordic Uhr; S.A.M.; Saab; Scania; Thulin; Tidaholm; Tjorven (sold as Kalmar on the export market); Volvo; And Yugo.

Catalysis or filter and sound damper

In a kind of embodiment, the invention still further relates to a kind of catalytic muffler, described catalytic muffler comprises catalysis of the present invention or filtering substrate.As described herein, described catalyst substrates or filtering substrate are in silencer is contained in a jar.

In a kind of embodiment, catalytic muffler of the present invention comprises the catalytic muffler of Known designs, wherein replaces the prior art catalyst substrates with catalyst substrates of the present invention.The known catalytic muffler that is fit to comprises US 6,622,482; 6,604,6004; 6,341,662; With 4,457, those disclosed in 895.

Gas extraction system

In another embodiment, the present invention relates to a kind of gas extraction system, it comprises catalyst substrates of the present invention.Gas extraction system generally comprises many assemblies.Described gas extraction system comprises that engine and suitable direct exhaust leave the device of engine.

Described gas extraction system comprises the conduit that internal combustion engine and direct exhaust are discharged from the exhaust outlet of combustion chamber.The optional part of other of gas extraction system comprises exhaust manifold, silencer and blast pipe.

In another embodiment, the present invention relates to a kind of gas extraction system, it comprises filtering substrate of the present invention.

On the other hand, the present invention relates to a kind of improved gas extraction system, it uses catalyst substrates of the present invention.On the other hand, the present invention relates to a kind of improved gas extraction system, it uses filtering substrate of the present invention.

Gas extraction system of the present invention is fit to use with following any: 1) movably road engine, equipment and the vehicles comprise automobile and light truck; Highway and street motorcycle; Heavy-duty highway engine such as truck and bus; 2) movably non-road engine, equipment and the vehicles comprise compression ignition engine (agricultural, building, mining etc.); Small-sized spark ignition engine (hay mover, fallen leaves purging machine, chain saw etc.); Large-scale spark ignition engine (forklift, generator etc.); Marine diesel engine (commercial ship, amusement with diesel engine etc.); Spark ignition engine peculiar to vessel (ship, private ship etc.); The amusement vehicles (snowmobile, cross country motorcycle, all-terrain vehicle etc.); Locomotive; Aviation instrument (ROV, ground-support equipment etc.); With 3) stationary source, it comprises hundreds of sources, as power plant, refinery and manufacturing facility.In another embodiment, the present invention relates to a kind of gas extraction system, it comprises base material of the present invention, catalytic converter, particulate filter or catalytic muffler.

Other gas extraction system of the present invention that is fit to comprises those that use in some sea-freight vehicles.Catalyst typically is arranged in the blast pipe of drawing from engine.This blast pipe is by the outlet of the guiding of the cabin in the hull near stern.This layout causes this blast pipe to vibrate easily, especially uses under the situation of prior art base material.In addition, in private ship, the limited size with the maintenance ship in space that can place engine is little low with center of gravity.And some prior art base material such as cordierite can not be too near to engine (may overheated and melt).The gas extraction system that comprises the sea-freight vehicles of catalytic converter of the present invention or particulate filter can overcome one or more of these problems.Described catalytic converter or particulate filter can place in the boats and ships gas extraction system and traditional converter or the identical position of filter, perhaps can be placed on other position.For example, in some embodiment, described catalytic converter is littler than prior art catalytic converter, but remove and/or the efficient of filtering contaminants basic identical.Referring to for example US 5,983,631 (YamahaHatsudoki Kabushiki Kaisha).

In other embodiment, gas extraction system of the present invention comprises one or more additional after-treatment devices or method, is used for reducing or limiting the pollutant that described gas extraction system is discharged.The apparatus and method that are fit to comprise CRT, EGR, SCR and ACERT etc.For example, in a kind of embodiment, described gas extraction system comprises catalytic converter of the present invention and CRT.Described gas extraction system can also comprise the SCR system.Other combination and variation also are possible and are interpreted as within the scope of the present invention.

In another embodiment, the present invention relates to a kind of gas extraction system, it comprises the NOx absorber, and described absorber has the catalyst substrates that comprises nSiRF-C composite and catalyst.Described main catalytic converter partly or entirely is positioned at the engine head.In a kind of embodiment, described main catalytic converter comprises catalyst substrates of the present invention, and the density of wherein said base material is about 12lb/ft ³, porosity is about 97%, its thermal expansion is low, structural intergrity is high and thermal conductivity is low.In a kind of preferred embodiment, described main catalytic converter comprises about 600cpsi, and wall thickness is the base material of about 6 mils.Main catalytic converter described in this embodiment has wall stream configuration.In a kind of preferred embodiment, described main catalytic converter has passage.In a kind of preferred embodiment, the passage of the catalyst substrates of described main catalytic converter is made with the comb platen press.In addition, in this embodiment, described catalyst substrates comprises optional wash coat.In this embodiment, oxidation and reduction that described main catalytic converter can the catalysis pollutant, for example have can oxidize contaminants catalyst, can go back the catalyst of parent pollutant in addition.In a kind of preferred embodiment, described NOx combination exhaust system comprises the expansion bed course.Described main catalytic converter can be used for all internal combustion engines.Described NOx combined system is preferably used under the situation that does not have the fuel carried catalyst.Usually, there is near the base material that is positioned at the silencer in described NOx combination exhaust system, but also can in other position.

Vehicle

In another embodiment, the present invention relates to a kind of improved vehicle, described improvement comprises according to catalytic converter of the present invention or particulate filter.In various embodiments, described improvement vehicle comprises any specific embodiments of catalytic converter described herein and particulate filter.

The exemplary refinement vehicle that is fit to comprises the vehicle that following one or more company makes: Daimler-Chrysler; Chrysler; Dodge; Eagle; Jeep; Plymouth; GeneralMotors; AM General (for example HUMMERs); Buick; Cadillac; Chevrolet; Geo; GMC; Hummer; LaSaIIe; Oldsmobile; Pontiac; Saturn; Ford; Continental; Lincoln; Mercury; Ace Motor Corp; American Motors; Avanti BMW; Daimler-Chrysler; Fiat; Ford; GAZ; General Motors; Honda; Mitsubishi; Renault; Peugeot; Toyota; Volkswagen Group; And Yugo.

Embodiment

Embodiment 1

The time of staying or the time of burnouting are that the hydrocarbon that constitutes exhaust pollution is retained in the time quantum of finishing burning or oxidation in the waste gas filter.The described time of staying of the present invention is significantly better than conventional system.Figure 19 provides respectively under the temperature of 600K, 900K, 1000K and 1200K burning or lights the curve map 1902,1904,1906,1908 of the required time of staying of cigarette ash.The kinetic energy that particle had is many more, and the possibility that success is reacted is high more.As shown in figure 19, under the temperature of 600K burning or time of staying 1902 of cigarette ash of lighting cigarette ash quality 0.9 than much longer in the time of staying 1908 of 1200K.The time of staying is long more, and admissible throughput is more little, and more particles accumulate in the filter hole and the danger in blocking filter hole is big more.Stopping up also may be the result that ceramic material is superheated to melting point, thereby blocks or the blocking filter hole.Time of staying value the 1902,1904, the 1906th, the feature of cordierite sample.The time of staying 1902,1904,1906 of completing combustion is in about 2 minutes to 20 hours scope.The time of staying 1908 is represented one embodiment of this invention, and completing combustion only needs about 0.75 second.

Embodiment 2

Base material

Preparation base material 1-7 as described herein.AETB-12 is available from COI Ceramics, with the nSiRF-C material that elects, density 12lbs/ft ³Be that 8 * 8 * 4 AETB-12 blank is inlayed sharp processing method machining base material/filter with the described standard carbide of this patent drill bit by measurement size.Described base material is processed into the cylindrical of following size: 2 inches of radiuses, 1 inch of longitudinal length.

With in base material, getting out through-flow/wall circulation road through-flow, that wall flows and mixes with standard C NC boring method known in the art described in this patent." the stainless steel drill bit of diameter is with 10, and 000RPM gets out these passages with 0.042.Observe in the boring procedure: because the thermal emissivity rate and the thermal conductivity height of material, drill bit is in hot environment, causes drill bit to damage and final fusing.Wall-thickness measurement not.

Base material 1 and 2 has through-flow configuration.Base material 3-6 has wall stream configuration.Base material 3 have an appointment 25% through-flow type passage and about 75% wall flow pattern passage.Base material 4 have an appointment 50% through-flow type passage and about 50% wall flow pattern passage.Base material 5 and 6 have an appointment 75% through-flow type passage and about 25% wall flow pattern passage.

Some base materials are coated with alumina washcoat, are Pt then: the Rh ratio is 5: 1 a catalyst coat.Particularly, base material 1,2 and any chemical substance of 7 uncoateds.Base material 3,4,5 and 6 usefulness standard technique known in the art are coated with uniform wash coat.Be entitled as to the quality of the wash coat of each base material coating in quality one hurdle of wash coat and providing.After described wash coat, comprise 5 with standard to base material 3,4,5 and 6 coatings: the catalyst mixture of 1Pt/Rh.The quality of the catalyst mixture that applies in each base material/filter is being entitled as the quality (g/ft of catalyst ³) provide in the hurdle.There is the base material of wash coat and noble metal catalyst load canned with the known technology of prior art.

Base material number	The weight of butt material (g)	The wet patch washcoat layer		The estimator g/in of wash coat 3	(g) of sintering	Quality (the g/in of wash coat 3)	H 2The O absolute value		Wet (GMS)	The quality of catalyst (g)
											GMS	NET	Weight in wet base (GMS)	H 2O absolute value (GMS/IN 3)
		1	29.0				178.5	149.4							2.91	63.0	2.71			---	---
2	28.9			182.0	153.1	2.99			65.3	2.90
		3	30.0				158.0	128.0							2.50	61.0	2.50	167.4	8.47	164.9	24.3Pt，4.8Rh
4	30.4			163.3	132.9	2.59			61.9	2.51	168.4	8.50	155.1	21.8Pt，4.4Rh
		5	30.3				165.7	135.4							2.64	62.0	2.52	169.8	8.58	170.4	25.3Pt，5.1Rh
6	30.9			184.6	153.7	3.00			67.3	2.90			202.5	31.6Pt，6.3Rh
																			Mean value=8.52 S/D=0.23 N=3		Mean value=30.9 S/D=5.0 N=4
7	24.3			105.1	80.8	2.47			44.6	2.54			99.7	20.2Pt，4.0Rh

Embodiment 3

The preparation of catalysis and filtering substrate

Prepare base material/filter fully as described in example 2 above, unless clearly mention.

With the remarkable difference of base material/filter described in the embodiment 1 in, ultimate depth is 3/4 inch in 1 inch semi-finished product, from CNC, take off described comb assembly and opposite (mirror image) comb assembly is installed, adopt identical stepping expanding method at the CNC stamping machine.The final result of this processing method is 600cpsi, and the wall stream of the wall of 6 mils and 1/2 inch is overlapping.As shown in Figure 28, the size of base material/filter is that 1 " diameter * 1 " is thick in the wall stream configuration, and the pattern of this semi-finished product inside is 0.8 " * 0.8 " square.Carrying out early stage successful Δ P with this base material tests and observes N ₂Pressure drop due to the flow obstacle that air-flow causes because of wall stream configuration.Figure 29 illustrates the pressure drop of measuring under 27 ℃, 29 ℃ and the 400 ℃ of temperature function with gas flow rate in reactor tube flow measurement system.Figure 30 is illustrated in the pressure drop of measuring under the constant flow rate of 125SLPM with variation of temperature in same reactor.These initial results are positive, represent that described nSiRF-C base material/filter does not produce very high back pressure in wall stream configuration.

Embodiment 4

The preparation of catalysis and filtering substrate

Prepare base material/filter fully as described in example 12 above, unless clearly mention.

In the remarkable difference of base material among the embodiment 1, use the density of buying from COI Ceramics to be respectively 11,12 and 16lbs/ft ³Blank AETB-11, AETB-12 and AETB-16 produce three kinds of different base materials.

For the base material/filter that is produced by AETB-11, ultimate depth is 3/4 inch in 1 inch semi-finished product, takes off described comb assembly and at the CNC stamping machine opposite (mirror image) comb assembly is installed from CNC, adopts identical stepping expanding method.The final result of this processing method is 600cpsi, and the wall stream of the wall of 6 mils and 1/2 inch is overlapping.For the base material/filter that produces by AETB-12 and AETB-16, ultimate depth is 7/8 inch in 1 inch semi-finished product, from CNC, take off described comb assembly and opposite (mirror image) comb assembly is installed, adopt identical stepping expanding method at the CNC stamping machine.The final result of this processing method is 600cpsi, and the wall stream of the wall of 6 mils and 3/4 inch is overlapping.

The size of all base material/filters of this stage test all is that 1 " diameter * 1 " is thick.These base materials are tested through another early stage Δ P observed pressure drop that base material density and wall stream configuration is observed variation with the hourly space velocity degree.Should concrete test under 932  temperature, carry out.Result of the test is shown among Figure 31.Except that AETB-11, AETB-12 and the data of AETB-16 base material/filter observation to us, Corning has reported the result of its 400/6.6 through-flow type cordierite substrates/filter and 200/12 cordierite DPT (wall stream configuration).The Corning data obtain by the Corning technical report.Though our result shows that the Corning DPT of wall stream configuration compares with the through-flow type filter of cordierite and produces too high back pressure, and our nSiRF-C filter even when using with wall stream configuration, also produce and the suitable back pressure of the through-flow type base material of cordierite.Deducibility since among the wall flow pattern DPTs back pressure be big problem, as observing among Figure 31, and invent as the present invention, the wall flow pattern DPTs that employing nSiRF-C material is made becomes splendid selection scheme.In addition, also observe back pressure and AETB-12 and the AETB-16 base material/filter contrast observed with AETB-11 base material/filter, the length that we can know increase " overlapping " passage by inference causes the back pressure performance better.

Figure 32 is the identical test of carrying out under the operating temperature of 1100 , and trend much at one as a result.

Embodiment 5

The preparation of catalysis and filtering substrate

Prepare base material/filter as described in example 2 above, unless clearly mention.

AETB-12 is available from COI Ceramics, as the nSiRF-C material of selecting, density 12lbs/ft ³The test laser-based drills through the hole that technology produces 3000cpsi and 30000cpsi.Adopt the DPSS laser system boring of describing in this patent and the related art.The hole that produces with the high energy laser system of pulse is foursquare, because this particular configuration, surface area is very high.With with Δ P test that flowing test reactor identical described in the embodiment 3 carries out in, it is conspicuous having very high surface area (channel wall thickness value greatly due to).It is successful observing the initial stage prototype that produces with the laser-based drilling technique, must make the Δ back pressure be less than the value of 10 inches water.Can further revise to reduce (or raising) hole density and to change wall thickness according to the needs of using.

It is that the pressure of AETB-12 base material/filter of 30000cpsi changes with N that Figure 33 is illustrated under 27 ℃ and 400 ℃ for hole density ₂The variation of gas velocity.It is that AETB-12 base material/filter of 30000cpsi is in different N that Figure 34 illustrates for hole density ₂The gas velocity downforce changes the variation with operating temperature.

It is that the pressure of AETB-12 base material/filter of 3000cpsi changes with N that Figure 35 is illustrated under 29 ℃ and 400 ℃ for hole density ₂The variation of gas velocity.

Embodiment 6

Diesel particulate filter

Produce base material and make about 13 inches of about 8 pounds/cubic feet size of density * about 13 inches * about 5 inches blank with the AETB prescription.From this blank, cut out the cylindrical semi-finished product of about 6 inches high 5 inches of diameters with diamond point saw.This base material further is being machined to precision tolerance (in the .001 inch) on the buldging lathe.

In described base material, form a plurality of passages then to make the base material that wall stream configuration is arranged that contains 600 passages per square inch.These passages are united boring and are combed the formation of pressure technology with described herein.Described passage is the square that is of a size of about 6 mils * 6 mils.The adjacent wall of adjacency channel is parallel to each other basically.Described passage does not run through the whole length of base material and is about 4.9 inches long.

Embodiment 7

The measurement of total surface area

The first and second cordierite samples have 33.2 and 46.97 square inches/cubic inch total surface area respectively.Therefore, in 1 inch cube of the first cordierite sample, 33.20 square inches area load noble metal is arranged.The total surface area of base material sample of the present invention is 83.58 square inches/cubic inch.

The general wall volume of the first and second cordierite samples is 0.311in ³/ in ³(cubic inch/cubic inch).The general wall volume of base material of the present invention is 0.272 cubic inch/cubic inch.Though the value of being somebody's turn to do is littler than the first and second cordierite samples, porosity of the present invention and permeability are much higher, make this less general wall volume more effective.

Embodiment 8

Activity test

The activity test measurement enters and leaves the amount of pollutant of filter.In activity test, sample filter is placed in the reactor, the gas of pumping known flow rate and temperature is by this material.The amount of pollutant of discharging is measured in activity test from filter then.Referring to Figure 24, the activity test of example base material 2410 of the present invention and cordierite sample 2420 is shown.This experimental measurement concentration 500ppm and air speed 40,000hr ^-1The activity of toluene.The hole density of two samples is 400cpsi.

This test explanation base material 2410 of the present invention is faster and in significantly lower temperature than the duration of ignition of cordierite sample 2420.Base material 2410 was reaching 85% damage in about 3 to 4 seconds under the temperature of about 335 .Cordierite 2420 is issued to 85% at about 380  and damages.Base material 2410 was reaching 90% damage in about 4 to 5 seconds under about 360 .Cordierite 2420 was reaching 90% damage in about 8 seconds under about 450 .Base material 2410 was reaching basic 100% burning in about 5 seconds under about 425 .Estimate that cordierite 2420 was reaching basic 100% damage under about 800  in about 28 seconds.

Embodiment 9

The permeability of catalyst substrates

The permeability of the example embodiment of the embodiment of the invention 2 is about 1093cd (a li darcy).Other test value surpasses the maximum that testing arrangement is measured.Compare with conventional system, the permeability of cordierite sample is about 268cd.

Embodiment 10

The catalytic converter of test implementation example 2

Be similar to activity test, EPA adopts the test that is called federal test method (" FTP ") 75, and the filter actual installation is being driven this car on the tailpipe of automobile and under rated condition.EPA is with the discharging of this verification experimental verification vehicle.The situation of FTP 75 testing vehicles under three kinds of states.First kind of state comprises that crank turned round 505 seconds under non-idling.This state reflection engine and emission control systems be entry into service and situation about midway not experienced up to stroke when the stroke of optimum level operation (be that catalyst is cold, do not reach effective control from the discharging of engine required " igniting " temperature) begins at ambient temperature.Second kind of state is included in and travelled under the non-idling 864 seconds, and be flame-out, sampling in other 5 seconds.Turn round the continuously situation of engine when the long enough time, all systems all reached the stable operation temperature of this state reflection vehicle.Vehicle has the wet machine time between 540 seconds and 660 seconds then.This wet machine time reflection is cut off and uncolled engine conditions to environmental condition.The third state is that crank turned round 505 seconds under non-idling.In these cases, engine and catalyst are warm, although be not in high workload efficient when starting, significantly improve with respect to the cold discharge performance that opens for the mode.

Embodiment 11

The heat test of catalyst substrates

The thermal conductivity of example embodiment of the present invention is about 0.0604W/m-K (energy of every meter thickness and every K variations in temperature (watt)).Compare, the cordierite sample is about 1.3 to 1.8W/m-K.These results show: if 1000 watts of heat energy of the cordierite material of given volume loss, then the material of the present invention of equal volume only loses 33 watts.Therefore, the thermal conductivity of material of the present invention is 30 times of cordierite.

The specific heat of example embodiment of the present invention is about 640J/kg-K (joule/kilogram-Kai).The cordierite sample is about 750J/kg-K.Even cordierite has bigger specific heat, cordierite filters also has bigger quality to heat.The result is that to reach the required heat energy of operating temperature more, makes the more poor efficiency of cordierite.

Repeatedly the serviceability temperature limit is the maximum temperature that material can stand repeatedly not have any degeneration.Base material can continue to work and not have the temperature of fine fisssure or spallation high more, and the possibility that base material ruptures along with the time or breaks is more little.This means that again base material is more durable in wideer temperature range.The temperature limit is higher to be preferred.

The repeatedly serviceability temperature of example embodiment of the present invention is limited to 2,980 ℃.The cordierite sample is about 1,400 ℃.Therefore, material of the present invention can stand the many temperature of twice of cordierite before breaking.This can work this material in wider exhaust environment.

Hot expansion system be given intensification (being generally 0 to 1 ℃) down length (linear coefficient), area (surface) or the volume of object increment respectively with the ratio of raw footage, area or volume.The ratio of these three coefficients is about 1: 2: 3.Do not have when clearly representing, mean the coefficient of cubical expansion usually.Base material expands fewly more during heating, and the possibility that filter assemblies leaks, breaks or damages is more little.Even preferred thermal expansion is low to guarantee that base material keeps its size when heating or cool off.

The thermal coefficient of expansion of example embodiment of the present invention is about 2.65 * 10 ^-6W/m-K (watt/Mi-Kai).The cordierite sample is about 2.5 * 10 ^-6W/m-K to 3.0 * 10 ^-6W/mK.Material coefficient of thermal expansion of the present invention is less than 10 times of cordierite.

In a kind of embodiment, the thermal coefficient of expansion of the base material preferably hot expansion system with wash coat is suitable.If hot expansion system dissmilarity, wash coat with spallation, layering, " peeling off " or disengaging base material, cause noble metal to be blown away or stop up hole.This will finally cause, and back pressure increases, the overheated and system failure.

Embodiment 12

Structural intergrity

The stretch modulus of AETB-12 is about 2.21MPa (a MPa pressure, approximate one atmospheric 100,000 times).The cordierite sample is about 25.0Mpa.Though about 10 times strong of cordierite, material of the present invention can tolerate 200,000 atmospheric pressure before breaking.This value is enough for application described herein.

Embodiment 13

Acoustic experiment

Acoustic attenuation may be defined as thickness, thinness, thin degree and reduces; Density reduces; Power or intensity reduce; Perhaps reduction.In a kind of embodiment of the present invention, described acoustic attenuation is the ability that base material weakens or weaken acoustic energy in the engine exhaust.Base material of the present invention can replace or cooperate the muffler assembly (as disclosed herein) of engine, thereby reduces exhaust noise and gas extraction system cost.Acoustic attenuation is higher to be preferred.

The generally acknowledged laboratory test that also not can be used at present any configuration of the present invention.All acoustic experiments of American Society for Testing Materials (" ASTM ") all are used for large space such as soundproof room but not are used for material.But in adopting the simple experiment of phonmeter, automobile noise is littler at least 25 decibels than conventional vehicle of eliminating the noise when finding to use in the gas extraction system base material of the present invention.As a reference, 110 decibels is the level that causes people's ear permanent damage, and 60 decibels is that vehicle window is rolled the noisiness in the luxury car of time idle running.

Embodiment 14

Contrast with the prior art base material

Multiple attribute is measured in nSiRF-C (AETB-12) sample that is suitable for and cordierite and SiC contrast.

	AETB-12	Cordierite	Carborundum (SiC)
				Thermal conductivity	6.04×10 -2W/m-K	1.3-1.8W/m-K	20W/m-K
Specific heat	640J/kg-K	750J/kg-K	950J/kg-K
				Density	0.2465gm/cc	2-2.1gm/cc	3.2gm/cc
Radiance	0.88	.13	.90
				Axial strength	2.21MPa	2.5MPa	18.6MPa
Noise attentuation under 3500rpm	74db	100db	100db
				Porosity	97.26％	18-42％	30-40％
Permeability	1093-∞cd	268cd	6.65cd
				Recovery time	0.75 second	2 minutes-20 hours	50 seconds-20 hours
Surface area	88,622in 2	847in 2	847in 2
				Fusing point	3,000℃	1,400℃	2400
Thermal expansion (CTE)	0.25×10 -71/C	0.7×10 -61/C	4-5×10 -61/C

Embodiment 15

In a kind of embodiment, base material of the present invention has the wall of 600cpsi and 6 mils.Hole density and two kinds of cordierite sample contrasts with base material sample of the present invention.First and second kinds of cordierite samples are respectively 100cpsi, wall thickness 17 mils and 200cpsi, wall thickness 12 mils.Base material of the present invention has the wall of 600cpsi and 6 mils in this embodiment.

In this example embodiment, described base material is drilled with the passage of 0.04 inch diameter, is spaced apart 0.06 inch across whole filter.These passages are littler than traditional cordierite.It is a lot of that the result is that the surface area ratio cordierite increases, even do not consider the surface area that exists in the macrovoid of base material.Described passage is preferably " blind " passage.Force waste gas to pass conduit wall, but not with under the situation of catalyst reaction do not flowing into and flow pass.

Get out passage with the CNC rig, this rig is computer-controlled to be consistent.Described boring procedure carries out under constant spray flux to prevent that dust gas carries, and this has OSHA danger, may enter the rig bearing and damages rig.

Bore the back base material and before applying any catalyst, remove or cure any water or other liquid that may exist in the hole at the baking oven inner drying.The time of curing is not variable, can determine evaporation of water by the weight of weighing base material simply.The time of curing is mainly quickened dehydration.After filter element heated with several different time intervals, weight was stable, and then base material prepares to be used to apply any catalyst or coating.

Nomenclature

Term used herein " base material " means the surface of solids that pollutant can be changed into the uncontamination thing thereon.Base material is understood to include filter cell, catalyst substrates or filtering substrate.

Term used herein " sintering " means the unfused material through heating.

Term used herein " non-woven " means that fiber does not interweave or is staggered.

Term used herein " blank " means not moulding or unprocessed host material piece.

Term used herein " green compact " means uncured blank.

Term used herein " front surface " means fluid and enters the surface that base material passes through.In some embodiment, passage front surface table has opening and channel vertical in front surface.

Term used herein " rear surface " means fluid and leaves the surface that base material passes through.In some embodiment, there are opening and channel vertical in the passage rear surface in the rear surface.

Term used herein " mil " means a kind of linear module, equals mil.

It is 50% o'clock temperature that term used herein " firing temperature " means catalytic converter internal reaction conversion ratio.Be that described firing temperature is the temperature that 50% one or more pollutants or gross contamination thing change into the uncontamination thing.

The particle that base material filters and the process of other substance combustion of meaning " burnt " in term used herein.For example, in diesel particulate filter (DPF), may burnout.

Term used herein " passage " means at least a portion that runs through base material in the base material and the three-dimensional opening of definite shape and length is arranged.

Term used herein " passage/square inch " means the port number that exists in one square inch of cross section of base material.Term hole/square inch is a synonym.

Term used herein " channel shape " means the 3D shape of passage.

Term used herein " PM " means particle.Common PM tolerance comprises PM-10 and PM-2.5.

Term used herein " total surface area " is total surface area, represent one cubic inch in noble metal can flood thereon total surface area.

Term used herein " economic benefits and social benefits catalytic converter " means and only makes gas phase pollution HC and CO be oxidized to CO ₂And H ₂The catalytic converter of O.

Term used herein " triple effect catalytic converter " means and makes CO and HC be oxidized to CO ₂And H ₂O but also make NOx be reduced into N ₂Catalytic converter.

Term used herein " quadruple effect catalytic converter " means to be finished at the described oxidation of triple effect catalytic converter and reduction but also captures the catalytic converter that particle is burnt it (can initiatively or passive mode regenerate).

Term used herein " is suitable for " to mean and satisfies concrete management principle requirement.

Term used herein " thermal conductivity " means under the situation that opposite face at sheet material is in unit temperature gradient (for example unit thickness temperature difference 1 degree) in the unit interval heat that the plate through the given material of unit are transmits.

Term used herein " bed course " generally means to base material and insulation is provided and/or protects employed any material.Bed course is also referred to as cotton-wool sometimes.

Term used herein " boron adhesive " means the reagent of being derived by the boron adhesive that exists among the nSiRF-C after the sintering process.

Term used herein " stepping " means by repeatedly forcing tip to enter and leaving host material and forms or transform passage until the process that obtains the length passage of wanting in base material.

Described the present invention now fully, those of ordinary skills should understand and can finish the present invention in the wide and equivalency range of the condition that does not influence the scope of the invention or its any embodiment, prescription and other parameter.All patents and the publication quoted herein all are incorporated herein for reference.

Claims (47)

1. catalysis or filtering substrate, it comprises non-woven sintering refractory fibre ceramic composite and catalyst, also comprises wash coat alternatively, and also comprises a plurality of passages alternatively.

2. the catalyst substrates of claim 1, wherein said composite comprises aluminium oxide-boron oxide-silicon dioxide fibre.

3. the catalyst substrates of claim 1, wherein said composite comprises aluminium oxide-zirconium oxide fibres.

4. the catalyst substrates of claim 1, wherein said composite comprises aluminium oxide-boron oxide-silicon dioxide fibre and alumina fibre.

5. the catalyst substrates of claim 1, wherein said composite comprises alumina fibre.

6. the catalyst substrates of claim 1, wherein said composite comprises silicon dioxide fibre.

7. the catalyst substrates of claim 1, wherein said composite comprises aluminium oxide boron oxide silicon dioxide fibre, silicon dioxide fibre and alumina fibre.

8. the catalyst substrates of claim 1, wherein said composite comprise about 50% to about 90% silica, about 5% to about 50% aluminium oxide and about 10% to about 25% aluminoborosilicate.

9. the catalyst substrates of claim 1, wherein said composite are thermal boundary (AETB) composites that aluminium oxide strengthens.

10. the catalyst substrates of claim 9, wherein said AETB is selected from AETB-8, AETB-12 and AETB-14 and AETB-16.

11. the catalyst substrates of claim 1, wherein said composite comprise Orbital ceramic thermal barrier (OCTB) composite.

12. each catalyst substrates of claim 1-11, wherein said composite comprises the boron adhesive.

13. each catalyst substrates of claim 1-12, wherein said catalyst comprises metallic catalyst.

14. each catalyst substrates of claim 1-13, wherein said catalyst is selected from palladium, platinum, rhodium, their mixture and their derivative.

15. each catalyst substrates of claim 1-14, wherein said catalyst is with about 1g/ft ³To about 50g/ft ³Amount exist.

16. each catalyst substrates of claim 1-15, wherein said wash coat comprises aluminium oxide.

17. each catalyst substrates of claim 1-16, it comprises a plurality of passages that vertically run through described base material, and wherein said base material comprises wall stream configuration, through-flow configuration or their combination.

18. each catalyst substrates of claim 1-17, it has about 100 to about 100,000 passage/square inches.

19. each catalyst substrates of claim 1-18, it has about 600 passage/square inches.

20. each catalyst substrates of claim 1-19, wherein said passage comprises square, triangle, hexagonal shape, also has the rectangle of being essentially, trapezoidal or leg-of-mutton longitudinal cross-section shape.

21. each catalyst substrates of claim 1-20, its front face surface is long-pending to be about 1 square inch to about 50 square inches.

22. each catalyst substrates of claim 1-21, it is applicable to and is purchased catalytic converter or diesel oxidation catalyst (DOC).

23. each catalyst substrates of claim 1-21, it is fit to use with stationary engine.

24. each catalyst substrates of claim 1-21, it is applicable to front end catalytic converter, manifold catalytic converter or pre-catalytic converter.

25. each catalyst substrates of claim 1-21, its density are about 6 to about 16lb/ft ³

26. each catalyst substrates of claim 1-25, the radiance of wherein said base material is about 0.8 to about 0.95.

27. each catalyst substrates of claim 1-26, the porosity of wherein said base material is about 90% to about 99%.

28. each catalyst substrates of claim 1-27, it also comprises storage oxygen oxide.

29. each catalyst substrates of claim 1-28, the pressure drop that the pressure drop ratio cordierite that wherein said base material produces produces is low.

30. a catalytic converter, it comprises each catalyst substrates of claim 1-29.

31. the catalytic converter of claim 30, wherein said converter is adapted at using on the commercial vehicle.

32. the catalytic converter of claim 31, wherein said converter are selected from main catalytic converter, pre-catalytic converter, back catalytic converter or manifold catalytic converter.

33. a particulate filter, it comprises each catalyst substrates or filtering substrate of claim 1-29.

34. the particulate filter of claim 33, wherein said filter is a diesel particulate filter.

35. the method for a catalytic reaction, it comprises makes one or more fluid streams be exposed to each catalyst substrates or catalytic converter of claim 1-32.

36. according to the method for claim 35, wherein said fluid is the waste gas from internal combustion engine.

37. according to the method for claim 36, wherein said waste gas comprises one or more in six kinds of index pollutants.

38. the method for a filtering gas, it comprises makes one or more fluid streams be exposed to each filtering substrate, catalyst substrates, particulate filter or catalytic converter of claim 1-34.

39. according to the method for claim 38, wherein said fluid is the waste gas from internal combustion engine.

40. according to the method for claim 39, wherein said waste gas comprises one or more in six kinds of index pollutants.

41. according to claim 1-29 each catalysis or the preparation method of filtering substrate, it comprises: with many fire-resistant silicon dioxide fibres, fire-resistant alumina fibre and the heating of fire-resistant aluminoborosilicate fiber; Described fiber is mixed; Wash described fiber; Alternatively described fiber is cut into one or more length; With described chopped strand fusion or be mixed in the slurry; Regulate the viscosity of described slurry, preferably by adding thickener; Add dispersant; Described slurry is added in the mould; From described slurry, remove and anhydrate to form green compact; Described green compact are taken out from described mould; In baking oven,, preferably carry out drying in about 250 to about 500  temperature with described green compact drying; In baking oven, heat described green compact, preferred preheating and increase progressively heating in about 2000-2500 ; Process described blank alternatively; In described blank, form a plurality of passages alternatively; Add catalyst alternatively; Add wash coat alternatively to form described base material.

42. according to each the preparation method of filtering substrate of claim 1-29, it comprises: process a plurality of passages in non-woven sintering refractory fibre ceramic composite, wherein said processing comprises with the comb platen press and forms described passage or make described channel forming.

43. a filtering substrate, it is according to the method preparation of claim 42 or 43.

44. a composition, it comprises fire-resistant grade aluminum oxide fiber, fire-resistant grade silicon dioxide fiber, fire-resistant grade aluminum oxide boron oxide silicon dioxide fibre, water and catalyst.

45. the composition of claim 44, the average length of wherein said fiber are about 10 microns.

46. the composition of claim 44, wherein said aluminium oxide account for about 50-90% of inorfil mixture; Alumina fibre accounts for about 5-50% of inorfil mixture; With the about 10-25% of aluminium oxide boron oxide silica comprises.

47. comprising, an improved engine exhaust system, described improvement use each catalyst substrates, filtering substrate, catalytic converter or particulate filter of claim 1-34.

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