CN102430336B - Eliminate the preprocessor of nitrogen oxide - Google Patents

Eliminate the preprocessor of nitrogen oxide Download PDF

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CN102430336B
CN102430336B CN201110271339.1A CN201110271339A CN102430336B CN 102430336 B CN102430336 B CN 102430336B CN 201110271339 A CN201110271339 A CN 201110271339A CN 102430336 B CN102430336 B CN 102430336B
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carrier
metal
foam
catalyst
metallic
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CN102430336A (en
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张克金
米新艳
崔龙
王丹
张苡铭
杨彬
许德超
刘国军
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FAW Group Corp
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Abstract

The present invention relates to a kind of preprocessor eliminating nitrogen oxide, by foam metal carrier, metal profile, metallic support sheet, set bolt forms; It is characterized in that: metal profile, metallic support sheet and set bolt fixed foam metallic carrier, metallic support sheet is that one end is welded in metal profile in a zigzag, and the other end adopts set bolt fixed foam metallic carrier; Metal profile is the structure that punching press or drawing become bowl-type, and on foam metal carrier, coating is suitable for the catalyst with SCR operating mode.It is started with from optimization foam metal effect and structure, adopts the active catalyst of low precious metal content, completes the making of foamed metal structures unit, have very high practical value.Air-flow mixing for tail gas disperses and promotes that NO partial oxidation becomes the reaction of NO2, and meet the commercial car demand of state more than 4, simple process, efficiency is high, and cost is low.

Description

Eliminate the preprocessor of nitrogen oxide
Technical field
The present invention relates to the preprocessor eliminating nitrogen oxide, be applied to the post processing industry of vehicle exhaust.
Background technology
Current, the whole world faces the integration challenges of the energy and environment.In the technological means selection of the emission compliance of orthodox car, people still face many difficult problems, such as, how to select the aspect such as carrier and catalyst of post processing.
Post processing carrier is the key factor forming automobile-used post processing platform, and by the end of so far, in post processing carrier, the overwhelming majority is the ceramic monolith of import, and the mechanical strength of this ceramic monolith is slightly poor, is not too adapted to the actual conditions of China; Equally, ripe metallic carrier, also by external technology and patent monoply, becomes the key factor restricting Chinese post processing industry development.
Therefore, how obtaining low cost and high performance post processing carrier is the core content advancing this art progress.
Foam metal is a kind of physical function new engineering material integrated with architectural characteristic.Start metal foaming material development the beginning of the eighties in the world, metal foaming material possesses light weight, sound insulation, filtration and flame-retarding characteristic, has again very strong shock-absorbing and electromagnetic shielding action, therefore, is widely used in national defense industry.The 90's rose, and foam metal is applied to civilian industry, and such as, high-caliber nickel foam is applied to the preparation of industrial electric capacity and automobile super capacitance.At present, China's foam metal research and production technical merit occupy prostatitis, the world.
Analyze from structure and show with actual test, foam metal is optimal post-treating metal carrier, such as, structural strength is higher than ceramic monolith, and gas channel is disorderly, the most easily obtain the catalytic effect of anticipation, in addition, the coating of catalyst and construction technology are comparatively simple, therefore, select metal foam as carrier, possess theoretic advance; But, the disadvantage of foam metal is that price is high, average 250 ~ 350 yuan/liter, even higher, for the diesel vehicle of an engine displacement 10 liters, the volume of post processing carrier is needed to be about about 20 liters, therefore, if adopt the foam metal of 100% as carrier, only carrier part is just up to 5000 ~ 7000 yuan/car, after considering the cost of catalyst and encapsulation, just causing the cost of car load to raise cannot accept, and becomes the obstacle of foam metal application.
Therefore, the structural parameters optimizing foam metal carrier are key factors that can this material obtain batch application.
In fact, the design of the carrier that the SCR system of import is used and catalyst has strict regulation, such as, in the front end of SCR main carrier and catalyst, generally all installs the carrier with DOC effect and the catalyst of small size additional; And in order to avoid the effusion of NH3, generally install again the carrier with DOC effect and the catalyst of small size additional in the rear end of SCR main carrier and catalyst.For this reason, the preprocessor eliminating nitrogen oxide is used as the meaning that the front end of SCR or rear end ' DOC ' have reality.
Retrieve with SCR used carrier and catalyst, it is that raw material obtains SCR catalyst through the preparation of sol/gel method that CN200910233873.6 discloses a kind of soluble-salt of the soluble-salt of tetrabutyl titanate, n-butanol, deionized water, glacial acetic acid, manganese and cerium that adopts; CN201010509228.5 discloses a kind of method comprising the copper/zeolite catalyst of commercial catalyst with ammonia prepared and/or improve the SCR for nitrogen oxide; CN201010295353.0 discloses the catalyst system of two catalyst beds, and wherein the first catalyst bed is iron-beta-zeolite, and downstream second catalyst bed is the silver supported on aluminium oxide; CN201010281306.0 discloses a kind of multifunction catalyst block, comprise substrate, hydrolysis of urea catalyst, load on substrate, SCR (SCR) catalyst, load are on substrate, and carrier is wherein the ceramic monolith of wall-flow type, and catalyst is zeolite molecular sieve; CN201010279857.3 discloses a kind of preparation method of nano Ti-based montmorillonite Cu catalyst and the application in HC-SCR thereof; CN201010274007.4 discloses a kind of catalysts selective for removing nitrogen oxide in exhaust gas from diesel vehicle and preparation method thereof, forms catalytic active center by vanadium, zirconium, tungsten and titanyl compound; It is carrier that CN201010142137.2 discloses with nano TiO 2, and V2O5, CeO2, MnO2 and Fe2O3 are main active component, WO3 and MoO3 is cocatalyst component; CN200910219520.0 discloses a kind of with Ce doped Ti O2 low-temperature SCR catalyst that is carrier and preparation method thereof, and load MnOX is catalyst activity component; CN200910130469.6 discloses one and comprises the firstth district and second district's system, and wherein, the firstth district is made up of iron SCR catalyst, and the secondth district is made up of copper SCR catalyst, and the secondth district is positioned at the downstream in the firstth district, does not describe the feature of carrier; CN200780042847.4 disclose SCR catalyst comprise on the alumina support wolframic acid silver; CN200810227323.9 discloses the Fe-ZSM-5 molecular sieve catalyst being prepared Large ratio surface by Two-step ion-exchanging method, then load minute amount of noble metal Pt on Fe-ZSM-5, obtained Pt x-Fe-ZSM-5 catalyst; CN200810137482.X discloses cellular metal screen catalyst by woven wire, deposition carrier on a wire mesh and the V of load on carrier 2o 5and MoO 3form;
Above-mentioned existing a lot of patent, all relate to the catalyst of SCR, but catalyst system is different from the present invention; Although also there is patent to describe carrier, be different from the present invention; Although also there is patent to describe the layout of carrier, be different from the present invention.
Given this, traditional SCR system faces many-sided problem, having larger improvement and the space of optimization, for reducing costs, raising the efficiency, and reduces problem of environmental pollution, creates the present invention.
Summary of the invention
The object of the present invention is to provide a kind of preprocessor eliminating nitrogen oxide, the air-flow mixing for tail gas disperses and promotes that NO partial oxidation becomes the reaction of NO2, and meet the commercial car demand of state more than 4, simple process, efficiency is high, and cost is low.
Of the technical scheme of the invention is that: after eliminating nitrogen oxides processors, with foam metal carrier, metal support plate, support plate, fixed bolts;Whose character is: the metal support plate, metal support pieces of foam and fixed bolt metal carrier, metal support for the zigzag, welding on the metallic support plate at one end, and the other end of the fixed bolt fixed foam metal carrier;Metal support plate is the structure of the stamping or drawing into a bowl, coating on metal foam carrier and working condition of SCR catalysts, the coated catalyst process is as follows: 1) the foam metal whole within the high temperature furnace, along with the furnace temperature of 450 ~ 550 ℃ and 40 ~ 60 min insulation, finished oil removal operation;2) in 1000 g of solid content of 15% wt commercial titanium sol additional add 400 ~ 480 g nano titanium dioxide, 480 ~ 580 g of deionized water and 100 ~ 580 g of alcohol, stir to form suspension liquid;3) the foam metal substrate immersed among them, take out after 3 ~ 50 min, compressed air purge excess liquid, 24 h at room temperature, then use compressed air purging flowing liquid.4) in the drying chamber, temperature 80 ℃, insulation 60 min;And then heating to 350 ~ 400 ℃, 100 ~ 120 min insulation;As a carrier of complete intermediate coating;5) additional in 1000 ml of distilled water to join 5 ~ 10% cerium nitrate, 10 ~ 20% of zirconium nitrate, 0.5 ~ 1% nitric acid platinum, 2 ~ 5% and 0.01 ~ 0.02% nitric acid alcohol, heat, stir to dissolve as the active catalyst solution;6) the activity of the catalyst solution spray to complete the carrier of the intermediate coating, coating on both sides, placed at room temperature of 120 ~ 300 min after out into a drying oven and 50 ℃ heat preservation 20 min, 40 min insulation under 80 ℃, 150 ℃ heat preservation under 100 min, 450 min under 450 ℃ heat preservation, along with the furnace cooling,Formed Ti Ce/Zr/Pt catalyst.
Good effect of the present invention is: start with from optimization foam metal effect and structure, adopts the active catalyst of low precious metal content, completes the making of foamed metal structures unit, have very high practical value.
Accompanying drawing explanation
Fig. 1 is structure chart of the present invention.
Fig. 2 is structure side view of the present invention.
Detailed description of the invention
Illustrate below in conjunction with accompanying drawing and with embodiment, the present invention to be further described: the preprocessor eliminating nitrogen oxide, by foam metal carrier 1, metal profile 2, metallic support sheet 3, set bolt 4 forms; It is characterized in that: metal profile 2, metallic support sheet 3 and set bolt 4 fixed foam metallic carrier, metallic support sheet 3 is that one end is welded in metal profile 2 in a zigzag, and the other end adopts set bolt 4 fixed foam metallic carrier 1; Metal profile 2 is structures that punching press or drawing become bowl-type, and on foam metal carrier 1, coating is suitable for the catalyst with SCR operating mode, and the technique of its coating catalyst is as follows:
(1) overall for foam metal in high temperature furnace, heat up 450 ~ 550 DEG C and be incubated 40 ~ 60min with stove, complete removal operation;
(2) at 1000g solid content be the alcohol additionally adding the nano titanium oxide of 400 ~ 480g, the deionized water of 500 ~ 580g and 100 ~ 180g in the commercially available titanium colloidal sol of 15%wt, stir and form suspension liquid;
(3) foam metal carrier is immersed, takes out after 3 ~ 50min, compressed air purges unnecessary liquid, and ambient temperatare puts 24h, then purges the liquid of trickling with compressed air;
(4) put into drying box, heat up 80 DEG C in proper order, insulation 60min; And then be warmed up to 350 ~ 400 DEG C, insulation 100 ~ 120min; As the carrier completing inter coat;
(5) additional in 1000 ml of distilled water to join 5 ~ 10% cerium nitrate, 10 ~ 20% of zirconium nitrate, 0.5 ~ 1% nitric acid platinum, 2 ~ 5% and 0.01 ~ 0.02% nitric acid alcohol, heat, stir to dissolve as the active catalyst solution;
(6) active catalyst solution is sprayed to complete on the carrier of inter coat, two sides sprays, after ambient temperatare puts 120 ~ 300min, move in drying box, 50 DEG C of insulation 20min, are incubated 40min at 80 DEG C, be incubated 100min at 150 DEG C, at 450 DEG C, be incubated 200min, cool with stove; Form Ti-Ce/Zr/Pt catalyst.
Embodiment, for illustrate feature of the present invention further, is not equal to restriction the present invention, for the change that those skilled in the art carries out according to the present invention, all should be included within protection scope of the present invention.
embodiment 1
Choose commercially available foam metal carrier, material is foamed aluminium, and order number is 5ppi[hole count per square inch], porosity for being greater than 80%, the foam metal that through-hole rate is greater than 90%, thickness 35mm, diameter is greater than gripper shoe perforate 60mm, diameter is 380mm, bores supported hole 6, uniform, overall for foam metal in high temperature furnace, heat up 450 DEG C and be incubated 60min with stove, complete removal operation, weigh W1=750g;
Be the alcohol additionally adding the nano titanium oxide of 450g, the deionized water of 550g and 50g in the commercially available titanium colloidal sol of 15%wt at 1000g solid content, stir and form suspension liquid;
by above-mentionedfoam metal carrier is immersed, and takes out after 20min, and compressed air purges unnecessary liquid, and ambient temperatare puts 24h, then purges the liquid of trickling with compressed air; Put into drying box, heat up 80 DEG C in proper order, insulation 60min; And then be warmed up to 350 DEG C, insulation 120min; As the carrier completing inter coat; Weigh W3=766g;
Additional add in 1000 ml of distilled water 50 g of cerium nitrate, 100 g of zirconium nitrate, 10 g of nitric acid platinum, 2 g of alcohol and 0. 1 g of nitric acid and heat until dissolved, as the active catalyst solution;
Active catalyst solution is sprayed to be completed on the foam carrier of inter coat, and two sides sprays, after ambient temperatare puts 120min, move in drying box, 50 DEG C of insulation 20min, are incubated 40min at 80 DEG C, be incubated 100min at 150 DEG C, at 450 DEG C, be incubated 200min, cool with stove; Form Ti-Ce/Zr/Pt catalyst.Weigh W5=774g;
Choose thickness be the metallic plate of 2mm stainless steel through the operation such as flange, punching, make metal profile, gripper shoe opening diameter 320mm; The metallic plate choosing thickness 3mm stainless steel prepares metallic support sheet after the operation such as bending, punching, one end welding of support chip on the supporting plate, foam metal carrier after the coating catalyst of Example 72, adopt set bolt to be fixed on 2 sides of gripper shoe, complete the making of foamed metal structures unit; The front end of the original SCR postprocessor on state 3 diesel engine of certain 9L, install foam metal unit of the present invention, carry out engine bench test, result shows, under different operating mode, raise without back pressure, NOX clearance improves 5 ~ 18%;
embodiment 2
Choose commercially available foam metal carrier, material is nickel foam, and order number is 35ppi[hole count per square inch], porosity for being greater than 80%, the foam metal that through-hole rate is greater than 90%, thickness 25mm, diameter is greater than gripper shoe perforate 60mm, diameter is 380mm, bores supported hole 6, uniform, overall for foam metal in high temperature furnace, heat up 550 DEG C and be incubated 40min with stove, complete removal operation, weigh W2=821g;
Be the alcohol additionally adding the nano titanium oxide of 450g, the deionized water of 550g and 50g in the commercially available titanium colloidal sol of 15%wt at 1000g solid content, stir and form suspension liquid;
Be immersed by above-mentioned foam metal carrier, take out after 50min, compressed air purges unnecessary liquid, and ambient temperatare puts 24h, then purges the liquid of trickling with compressed air; Put into drying box, heat up 80 DEG C in proper order, insulation 60min; And then be warmed up to 400 DEG C, insulation 100min; As the carrier completing inter coat; Weigh W4=905g;
Active catalyst solution is sprayed to be completed on the foam carrier of inter coat, and two sides sprays, after ambient temperatare puts 300min, move in drying box, 50 DEG C of insulation 20min, are incubated 40min at 80 DEG C, be incubated 100min at 150 DEG C, at 450 DEG C, be incubated 200min, cool with stove; Form Ti-Ce/Zr/Pt catalyst.Weigh W6=917g;
Choose thickness be the metallic plate of 2mm stainless steel through the operation such as flange, punching, make metal profile, gripper shoe opening diameter 320mm; The metallic plate choosing thickness 3mm stainless steel prepares metallic support sheet after the operation such as bending, punching, one end welding of support chip on the supporting plate, foam metal carrier after the coating catalyst of Example 82, adopt set bolt to be fixed on 2 sides of gripper shoe, complete the making of foamed metal structures unit; The front end of the original SCR postprocessor on state 3 diesel engine of certain 9L, install foam metal unit of the present invention, carry out engine bench test, result shows, under different operating mode, back pressure raises and is less than 1.5Kpa, and NOX clearance improves 9 ~ 24%.

Claims (1)

1. eliminate the preprocessor of nitrogen oxide, by foam metal carrier, metal profile, metallic support sheet, set bolt forms; It is characterized in that: metal profile, metallic support sheet and set bolt fixed foam metallic carrier, metallic support sheet is that one end is welded in metal profile in a zigzag, and the other end adopts set bolt fixed foam metallic carrier; Metal profile is the structure that punching press or drawing become bowl-type, and on foam metal carrier, coating is applicable to the catalyst of SCR operating mode, and the technique of its coating catalyst is as follows:
1) foam metal carrier in high temperature furnace, heat up 450 ~ 550 DEG C and be incubated 40 ~ 60min with stove, complete removal operation;
2) at 1000g solid content be the alcohol additionally adding the nano titanium oxide of 400 ~ 480g, the deionized water of 500 ~ 580g and 100 ~ 180g in the commercially available titanium colloidal sol of 15wt%, stir and form suspension liquid;
3) foam metal carrier is immersed, takes out after 3 ~ 50min, compressed air purges unnecessary liquid, and ambient temperatare puts 24h, then purges the liquid of trickling with compressed air;
4) put into drying box, heat up 80 DEG C in proper order, insulation 60min; And then be warmed up to 350 ~ 400 DEG C, insulation 100 ~ 120min; As the carrier completing inter coat;
5) additional in 1000 ml of distilled water to join 5 ~ 10% cerium nitrate, 10 ~ 20% of zirconium nitrate, 0.5 ~ 1% nitric acid platinum, 2 ~ 5% and 0.01 ~ 0.02% nitric acid alcohol, heat, stir to dissolve as the active catalyst solution;
6) active catalyst solution is sprayed to complete on the carrier of inter coat, two sides sprays, after ambient temperatare puts 120 ~ 300min, move in drying box, 50 DEG C of insulation 20min, are incubated 40min at 80 DEG C, be incubated 100min at 150 DEG C, at 450 DEG C, be incubated 200min, cool with stove; Form Ti-Ce/Zr/Pt catalyst.
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CN115254094B (en) * 2022-08-04 2024-07-26 安徽元琛环保科技股份有限公司 Preparation method of metal-based anti-knock denitration catalyst and prepared catalyst

Citations (4)

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Publication number Priority date Publication date Assignee Title
CN1360975A (en) * 2000-12-29 2002-07-31 中国科学院金属研究所 Prepn of three-effect automobile tail gas purifying catalyst on foamed ceramic carrier
EP1346769A1 (en) * 2002-03-13 2003-09-24 Capital Technology S.A. Device for the continuous burning of carbon particles
CN1542265A (en) * 2003-04-30 2004-11-03 比亚迪股份有限公司 Vehicle tail-gas catalytic converter
CN101172257A (en) * 2006-11-01 2008-05-07 张世臣 Bubble iron chromium aluminum applied in vent gas filtering and catalyst carrier, and production technique thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7527774B2 (en) * 2005-12-22 2009-05-05 Basf Catalysts Llc Inlet metallic foam support coupled to precious metal catalyst for application on 4 stroke platforms

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1360975A (en) * 2000-12-29 2002-07-31 中国科学院金属研究所 Prepn of three-effect automobile tail gas purifying catalyst on foamed ceramic carrier
EP1346769A1 (en) * 2002-03-13 2003-09-24 Capital Technology S.A. Device for the continuous burning of carbon particles
CN1542265A (en) * 2003-04-30 2004-11-03 比亚迪股份有限公司 Vehicle tail-gas catalytic converter
CN101172257A (en) * 2006-11-01 2008-05-07 张世臣 Bubble iron chromium aluminum applied in vent gas filtering and catalyst carrier, and production technique thereof

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