WO2016175737A1 - Catalyseur d'oxydation bicouche destiné à améliorer le rendement de soufre - Google Patents

Catalyseur d'oxydation bicouche destiné à améliorer le rendement de soufre Download PDF

Info

Publication number
WO2016175737A1
WO2016175737A1 PCT/US2015/027741 US2015027741W WO2016175737A1 WO 2016175737 A1 WO2016175737 A1 WO 2016175737A1 US 2015027741 W US2015027741 W US 2015027741W WO 2016175737 A1 WO2016175737 A1 WO 2016175737A1
Authority
WO
WIPO (PCT)
Prior art keywords
oxidation catalyst
catalyst
channel
layered
sulfur
Prior art date
Application number
PCT/US2015/027741
Other languages
English (en)
Inventor
Yi Liu
Arvind V. Harinath
Original Assignee
Cummins Emission Solutions, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Cummins Emission Solutions, Inc. filed Critical Cummins Emission Solutions, Inc.
Priority to PCT/US2015/027741 priority Critical patent/WO2016175737A1/fr
Publication of WO2016175737A1 publication Critical patent/WO2016175737A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9459—Removing one or more of nitrogen oxides, carbon monoxide, or hydrocarbons by multiple successive catalytic functions; systems with more than one different function, e.g. zone coated catalysts
    • B01D53/9477—Removing one or more of nitrogen oxides, carbon monoxide, or hydrocarbons by multiple successive catalytic functions; systems with more than one different function, e.g. zone coated catalysts with catalysts positioned on separate bricks, e.g. exhaust systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/103—Oxidation catalysts for HC and CO only
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2066—Selective catalytic reduction [SCR]
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/10—Noble metals or compounds thereof
    • B01D2255/102—Platinum group metals
    • B01D2255/1021—Platinum
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/10—Noble metals or compounds thereof
    • B01D2255/102—Platinum group metals
    • B01D2255/1023—Palladium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/207—Transition metals
    • B01D2255/20707—Titanium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/209—Other metals
    • B01D2255/2092—Aluminium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/90—Physical characteristics of catalysts
    • B01D2255/902—Multilayered catalyst
    • B01D2255/9022—Two layers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/90—Physical characteristics of catalysts
    • B01D2255/903—Multi-zoned catalysts
    • B01D2255/9032—Two zones
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/90—Physical characteristics of catalysts
    • B01D2255/915—Catalyst supported on particulate filters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/30—Sulfur compounds
    • B01D2257/302—Sulfur oxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2258/00—Sources of waste gases
    • B01D2258/01—Engine exhaust gases
    • B01D2258/012—Diesel engines and lean burn gasoline engines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2258/00—Sources of waste gases
    • B01D2258/01—Engine exhaust gases
    • B01D2258/018—Natural gas engines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9404—Removing only nitrogen compounds
    • B01D53/9409—Nitrogen oxides
    • B01D53/9431—Processes characterised by a specific device
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/944—Simultaneously removing carbon monoxide, hydrocarbons or carbon making use of oxidation catalysts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2370/00—Selection of materials for exhaust purification
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2510/00—Surface coverings
    • F01N2510/06—Surface coverings for exhaust purification, e.g. catalytic reaction
    • F01N2510/068—Surface coverings for exhaust purification, e.g. catalytic reaction characterised by the distribution of the catalytic coatings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Definitions

  • the present disclosure relates generally to exhaust aftertreatment systems for use with internal combustion (IC) engines.
  • IC internal combustion
  • Exhaust aftertreatment systems are used to receive and treat exhaust gas generated by IC engines.
  • Conventional exhaust gas aftertreatment systems include any of several different components to reduce the levels of harmful exhaust emissions present in the exhaust gas.
  • certain exhaust aftertreatment systems for diesel-powered IC engines and certain diesel and natural gas dual-fuel powered IC engines include a selective catalytic reduction (SCR) system to convert NOx (NO and N0 2 in some fraction) into harmless nitrogen gas (N 2 ) and water vapor (H 2 0) in the presence of ammonia (NH3).
  • SCR selective catalytic reduction
  • Aftertreatment systems can also include an oxidation catalyst (e.g., a diesel oxidation catalyst) positioned upstream or downstream of the SCR system for catalyzing the oxidation of carbon monoxide (CO), NO, hydrocarbons and/or ammonia in the exhaust gas.
  • Oxidation catalysts generally include precious metals, for example platinum (Pt) or palladium (Pd).
  • Pt platinum
  • Pd palladium
  • the SOx gases included in the exhaust gas can poison the precious metal oxidation catalysts.
  • the oxidation catalyst gradually loses its oxidation capability, leading to degradation and eventual failure of the oxidation catalyst. Summary
  • Embodiments described herein relate generally to aftertreatment systems having an oxidation catalyst assembly configured to trap SOx gases included in the exhaust gas to protect an oxidation catalyst of the aftertreatment system.
  • Particular variations of the aftertreatment systems described herein include an oxidation catalyst assembly which includes a sulfur catalyst layered on the oxidation catalyst for trapping SOx gases included in the exhaust gas.
  • an aftertreatment system comprises an oxidation catalyst assembly defining a channel for an exhaust gas to flow therethrough.
  • the channel has an inlet and an outlet.
  • the oxidation catalyst assembly includes a substrate, an oxidation catalyst, and a sulfur catalyst.
  • a SCR system is positioned downstream of the oxidation catalyst assembly.
  • the SCR system includes at least one catalyst formulated to reduce the exhaust gas.
  • the oxidation catalyst assembly is layered such that the oxidation catalyst is layered on the substrate.
  • the sulfur catalyst is layered on the oxidation catalyst so that the sulfur catalyst defines the channel.
  • an aftertreatment system comprises a first oxidation catalyst assembly which includes a first substrate, a first oxidation catalyst, and a first sulfur catalyst.
  • the first oxidation catalyst assembly defines a first channel for an exhaust gas to flow therethrough.
  • the first channel has a first channel inlet and a first channel outlet.
  • a SCR system is positioned downstream of the first oxidation catalyst assembly.
  • the SCR system includes at least one catalyst formulated to treat the exhaust gas.
  • a second oxidation catalyst assembly is positioned downstream of the SCR system.
  • the second oxidation catalyst assembly includes a second substrate, a second oxidation catalyst, and a second sulfur catalyst.
  • the second oxidation catalyst assembly defines a second channel for an exhaust gas to flow therethrough.
  • the second channel has a second channel inlet and a second channel outlet.
  • an oxidation catalyst assembly for use in an oxidation catalyst assembly
  • aftertreatment system comprises a substrate, an oxidation catalyst layered on at least a portion of the substrate; and a sulfur catalyst layered on at least one of the substrate and the oxidation catalyst.
  • the oxidation catalyst assembly defines a channel having an inlet and an outlet.
  • FIG. 1 is schematic block diagram of an embodiment of an aftertreatment system that includes a first oxidation catalyst assembly which includes a sulfur catalyst, a SCR system and optionally, a filter and/or a second oxidation catalyst assembly.
  • a first oxidation catalyst assembly which includes a sulfur catalyst, a SCR system and optionally, a filter and/or a second oxidation catalyst assembly.
  • FIG. 2 is a side cross-section of another embodiment of an oxidation catalyst assembly, which can be included in the aftertreatment system of FIG. 1.
  • FIG. 3 is a side cross-section view of yet another embodiment of an oxidation catalyst assembly.
  • FIG. 4 is schematic block diagram of still another embodiment of an aftertreatment system that includes a SCR system, a first oxidation catalyst assembly positioned upstream of the SCR system and a second oxidation catalyst assembly positioned downstream of the SCR system.
  • Embodiments described herein relate generally to aftertreatment systems having an oxidation catalyst assembly configured to trap SOx gases included in the exhaust gas to protect an oxidation catalyst of the aftertreatment system.
  • Particular variations of the aftertreatment systems described herein include an oxidation catalyst assembly which includes a sulfur catalyst layered on the oxidation catalyst for trapping SOx gases included in the exhaust gas.
  • Embodiments of the dual-layer oxidation catalyst described herein may provide several benefits including, for example: (1) providing a sulfur catalyst in an oxidation catalyst assembly of the aftertreatment system to trap SOx gases included in the exhaust gas; (2) layering the sulfur catalyst on an oxidation catalyst and/or a substrate of the oxidation catalyst assembly using conventional techniques; (3) preventing poisoning of the oxidation catalyst by the SOx gases by trapping the SOx gases included in the exhaust gas in the sulfur catalyst before the exhaust gas contacts the oxidation catalyst thereby, preventing or severely inhibiting degradation and extending the light of the oxidation catalyst; and (4) allowing regeneration of the sulfur trap catalyst by heating the sulfur catalyst in the presence of reducing agents.
  • FIG. 1 is a schematic block diagram of an aftertreatment system 100 according to an embodiment.
  • the aftertreatment system 100 includes a first oxidation catalyst assembly 110, a SCR system 150, and optionally, a filter 120 and a second oxidation catalyst assembly 160.
  • the aftertreatment system 100 is configured to receive an exhaust gas from an IC engine (not shown).
  • the exhaust gas can include, for example a diesel engine exhaust gas, a natural gas engine exhaust gas, a dual diesel-natural gas engine exhaust gas or a gasoline engine exhaust gas.
  • the exhaust gas includes a source of sulfur, i.e., SOx gases such as S0 2 , S0 3 and/or H 2 S.
  • the first oxidation catalyst assembly 110 is positioned upstream of the SCR system 150 and configured to receive the exhaust gas from the engine.
  • the first oxidation catalyst assembly 110 defines a channel having an inlet and an outlet to allow the exhaust gas to flow therethrough.
  • the first oxidation catalyst assembly 110 includes a substrate, an oxidation catalyst and a sulfur catalyst.
  • the first oxidation catalyst assembly 110 can include be layered, as described herein.
  • the first oxidation catalyst assembly 110 can have a honey comb structure.
  • the first oxidation catalyst assembly 110 can define a plurality of channels therewithin.
  • the substrate can include any suitable substrate such as, for example, a ceramic (e.g., cordierite) or metallic (e.g., kanthal) monolith core which can, for example, define a honeycomb structure.
  • the substrate can include a monolith substrate or a wall flow substrate.
  • the first oxidation catalyst can be layered on the substrate.
  • a washcoat can also be used as a carrier material for the first oxidation catalyst.
  • washcoat materials can include, for example, aluminum oxide, titanium dioxide, silicon dioxide, any other suitable washcoat material, or a combination thereof.
  • the oxidation catalyst is formulated to oxidize CO, NO and/or hydrocarbons included in the exhaust gas.
  • the oxidation catalyst can include precious metals such as Pt and Pd. These precious metals are susceptible to poisoning by SOx gases included in the exhaust gas which degrades the performance of the oxidation catalyst leading to eventual failure.
  • the sulfur catalyst is layered on the oxidation catalyst and/or the substrate, as described in greater detail herein.
  • the sulfur catalyst is formulated to trap all or substantially all of the SOx gases included in the exhaust gas, thereby preventing poisoning of the oxidation catalyst by the SOx gases.
  • the term "preventing" refers to a system that traps all or substantially all of the SOx gases included in the exhaust gas, meaning that it is possible for a certain amount of de minimis degradation to occur over an extended period of time as would be understood by one of ordinary skill in the art.
  • the sulfur catalyst is layered relative to the oxidation catalyst such that the SOx gases in the exhaust gas are trapped by the sulfur catalyst before the exhaust gas contacts the oxidation catalyst.
  • the sulfur catalyst can include any suitable sulfur catalyst.
  • the sulfur catalyst can include oxides of aluminum, calcium, sodium, magnesium, barium, potassium, copper, iron, cobalt, silver, manganese, cerium, platinum-barium alloy, cerium-zirconium alloy, cerium-iron alloy, manganese-lanthanum-zirconium alloy, iron-lanthanum-zirconium alloy, copper-lanthanum-zirconium alloy, cobalt-lanthanum-zirconium alloy, zeolites, perovskites any other suitable sulfur catalyst or any combinations thereof.
  • the sulfur catalyst includes a combination of iron oxide, aluminum oxide and calcium oxide (e.g., the sulfur catalyst available under the tradename SULFURTRAP®).
  • the sulfur catalyst can be regenerated by heating the sulfur catalyst to an elevated temperature in the presence of reducing agents.
  • the sulfur catalyst can be regenerated by heating to a temperature of 500 degrees Celsius in the presence of hydrogen and carbon monoxide.
  • the oxidation catalyst is layered on at least a portion of the substrate, and the sulfur catalyst is layered on at least one of the oxidation catalyst and the substrate.
  • the oxidation catalyst assembly 110 defines a channel therethrough having an inlet and an outlet.
  • the oxidation catalyst assembly 110 is layered such that the oxidation catalyst is layered on the substrate and the sulfur catalyst is layered on the oxidation catalyst.
  • the sulfur catalyst defines the channel. As the exhaust gas enters the channel, the exhaust gas diffuses through the sulfur catalyst which traps the SOx gases, before it contacts the oxidation catalyst. In this manner, the oxidation catalyst is protected from poisoning by the SOx gases.
  • the oxidation catalyst assembly 110 is layered such that the sulfur catalyst is layered on a first portion of the substrate proximal to the inlet and defines a channel first portion. Furthermore, the oxidation catalyst is layered on a second portion of the substrate proximal to the outlet and defines a channel second portion.
  • the exhaust gas contacts the sulfur catalyst as the exhaust gas enters the channel. Substantially all of the SOx gases in the exhaust gas are trapped in the channel first portion by the sulfur catalyst.
  • the length of the channel first portion can be defined to allow sufficient resident time of the exhaust gas in the channel first portion at a predetermined flow rate to allow trapping of substantially all of the SOx gases.
  • the exhaust gas is substantially free (i.e., includes less than 1%) of SOx gases.
  • the first sulfur catalyst can be mixed homogeneously with the oxidation catalyst to form a mixture which is layered on the substrate.
  • the SCR system 150 is positioned downstream from the oxidation catalyst assembly 110 and configured to receive the exhaust gas from the oxidation catalyst assembly 110.
  • the SCR system 150 is configured to treat the exhaust gas (e.g., a diesel exhaust gas) flowing through the SCR system 150.
  • the SCR system 150 can include one or more catalysts formulated to selectively reduce the exhaust gas. Any suitable catalyst can be used such as, for example, platinum, palladium, rhodium, cerium, iron, manganese, copper, vanadium based catalyst, any other suitable catalyst, or a combination thereof.
  • the exhaust gas can flow over and about the catalyst such that any NOx gases included in the exhaust gas are further reduced to yield an exhaust gas which is substantially free of carbon monoxide and NOx gases.
  • Trapping of the SOx gases by the sulfur catalyst in the first oxidation catalyst assembly 110 can also protect the catalyst included in the SCR system 150 from poisoning by the SOx gases. Furthermore, trapping of the SOx gases by the first oxidation catalyst assembly 110 can allow the aftertreatment system 100 or any other aftertreatment system in which the first oxidation catalyst assembly 110 is included to meet SOx emission regulations (e.g., US EPA 2013, China VI National Standard, India Bharat Stage V and European VI emission standards).
  • SOx emission regulations e.g., US EPA 2013, China VI National Standard, India Bharat Stage V and European VI emission standards.
  • a filter 120 can be positioned upstream of the SCR system 150 and downstream of the first oxidation catalyst assembly 110.
  • the filter 120 can comprise, for example a diesel particulate filter.
  • the filter 120 is configured to filter any particulate matter (e.g., carbon, soot, etc.) from the exhaust gas.
  • the filter 120 can be catalyzed.
  • the filter 120 can include a filter substrate, a filter oxidation catalyst layered on the filter substrate, and a filter sulfur catalyst layered on the filter oxidation catalyst.
  • the filter substrate, the filter oxidation catalyst and the filter sulfur catalyst can have the same composition as the first substrate, the first oxidation catalyst and the first sulfur catalyst of the first oxidation catalyst assembly 110.
  • the filter 120 can be used in place of the first oxidation catalyst assembly 110.
  • the filter 120 serves as a multipurpose apparatus for filtering particulate matter, trapping SOx gases and oxidizing CO, NO and/or hydrocarbons.
  • a second oxidation catalyst assembly 160 is positioned downstream of the SCR system 150.
  • the second oxidation catalyst assembly 160 can also include a substrate, an oxidation catalyst and a sulfur catalyst.
  • the second oxidation catalyst assembly 160 can be substantially similar to the first oxidation catalyst assembly 110.
  • the oxidation catalyst included in the second oxidation catalyst assembly 160 includes an ammonia oxidation catalyst.
  • FIG. 2 shows an oxidation catalyst assembly 210 according to one embodiment.
  • the oxidation catalyst assembly 210 can be used in an aftertreatment system, for example the aftertreatment system 100 (e.g., as the first oxidation catalyst assembly 110 or the second oxidation catalyst assembly 160) or any other aftertreatment system described herein.
  • the oxidation catalyst assembly 210 includes a substrate 212, an oxidation catalyst 214, and a sulfur catalyst 216, and defines a channel 211 having an inlet 213 and an outlet 215.
  • the substrate 212 is substantially similar to the substrate defined with respect to the first oxidation catalyst assembly 110 included in the aftertreatment system 100.
  • the oxidation catalyst 214 is layered on the substrate 212.
  • the oxidation catalyst is substantially similar to the oxidation catalyst described with respect to the first oxidation catalyst assembly 110 included in the first aftertreatment system.
  • the sulfur catalyst 216 is layered on the oxidation catalyst 214 so that the sulfur catalyst.
  • the sulfur catalyst 216 defines an inner most surface of the oxidation catalyst assembly 210 thereby defining the channel 211.
  • the sulfur catalyst 216 is substantially similar to the sulfur catalyst described with respect to the first oxidation assembly 110.
  • the exhaust gas enters the inlet 213 and comes in first in contact with the sulfur catalyst 216 defining the channel 211.
  • the sulfur catalyst 216 traps any SOx gases included in the exhaust gas.
  • the sulfur catalyst 216 can have a thickness which allows the exhaust gas to diffuse through the sulfur catalyst 216 to contact the oxidation catalyst 214. Substantially all of the SOx gases are trapped by the sulfur catalyst 216 before the exhaust gas contacts the oxidation catalyst 214. In this manner, the oxidation catalyst 214 is protected or substantially protected from poisoning by the SOx gases.
  • a length of the oxidation catalyst assembly 210 is defined such that by the time the exhaust gas exits the channel 211 via the outlet 215, substantially all of the SOx gases, NO, CO, hydrocarbons and/or ammonia are oxidized within the oxidation catalyst assembly 210.
  • FIG. 3 shows an oxidation catalyst assembly 310 according to another embodiment.
  • the oxidation catalyst assembly 310 can be used in an aftertreatment system, for example the aftertreatment system 100 (e.g., as the first oxidation catalyst assembly 110 or the second oxidation catalyst assembly 160) or any other aftertreatment system described herein.
  • the oxidation catalyst assembly 310 includes a substrate 312, an oxidation catalyst 314, and a sulfur catalyst 316, and defines a channel 311 having an inlet 313 and an outlet 315.
  • the substrate 312, the oxidation catalyst 314 and the sulfur catalyst 316 are substantially similar to the substrate, the oxidation catalyst and the sulfur catalyst defined with respect to the first oxidation catalyst assembly 110 described herein.
  • the oxidation catalyst assembly 310 is layered as shown in FIG. 3.
  • the sulfur catalyst 316 is layered on a first portion of the substrate 312 proximal to the channel inlet 313 and defines a channel first portion 317.
  • the oxidation catalyst 314 is layered on a second portion of the substrate 312 proximal to the channel outlet 315 and defines a channel second portion 319.
  • an aftertreatment system can include a first oxidation catalyst assembly and a second oxidation catalyst assembly.
  • FIG. 4 is a schematic block diagram of an aftertreatment system 400 according to another embodiment.
  • the aftertreatment system 400 includes a first oxidation catalyst assembly 410, a SCR system 450 and a second oxidation catalyst assembly 460.
  • the first oxidation catalyst assembly 410 includes a first substrate 412, a first oxidation catalyst 414 and a first sulfur catalyst 416.
  • the first oxidation catalyst assembly 410 defines a first channel 411 having a first inlet 413 and a first outlet 415.
  • the first substrate 412, the first oxidation catalyst 414 and the first sulfur catalyst 416 are substantially similar to the substrate, the oxidation catalyst and the sulfur catalyst defined with respect to the first oxidation catalyst assembly 110 described herein.
  • the first oxidation catalyst 414 includes a CO catalyst, a NOx catalyst and/or a hydrocarbon catalyst.
  • the first oxidation catalyst 414 is layered on the first substrate 412, Furthermore, the first sulfur catalyst 416 is layered on the first oxidation catalyst 414 so that the first sulfur catalyst 416 defines an inner most surface of the first oxidation catalyst assembly 410 which defines the first channel 41 1.
  • the SCR system 450 is positioned downstream of the first oxidation catalyst assembly 410.
  • the SCR system 450 includes a catalyst formulated to reduce the exhaust gas.
  • the SCR system 450 can be substantially similar to the SCR system 150 included in the aftertreatment system 100 and therefore, not described in further detail herein.
  • the second oxidation catalyst assembly 460 is positioned downstream of the SCR system 450.
  • the second oxidation catalyst assembly 460 includes a second substrate 462, a second oxidation catalyst 464 and a second sulfur catalyst 466.
  • the second oxidation catalyst assembly 460 defines a second channel 461 having a second inlet 463 and a second outlet 465.
  • the second substrate 462, the second oxidation catalyst 464 and the second sulfur catalyst 466 are substantially similar to the substrate, the oxidation catalyst and the sulfur catalyst defined with respect to the first oxidation catalyst assembly 110 described herein.
  • the second oxidation catalyst 464 includes an ammonia catalyst.
  • the second oxidation catalyst 464 includes a CO catalyst, a NOx catalyst and/or a hydrocarbon catalyst.
  • the second oxidation catalyst assembly 460 is substantially similar to the first oxidation catalyst assembly 410.
  • the second oxidation catalyst 464 is layered on the second substrate 462.
  • the second sulfur catalyst 466 is layered on the second oxidation catalyst 464 such that the second sulfur catalyst 466 defines an inner most surface of the second oxidation catalyst assembly 460, which defines the second channel 461.
  • the exhaust gas enters the first oxidation catalyst assembly 410.
  • Substantially all of the SOx gases included in the exhaust gas are trapped by the first sulfur catalyst 416 before the exhaust gas contacts the first oxidation catalyst 414. This protects the first oxidation catalyst 414 from being poisoned by the SOx gases.
  • the exhaust gas enters the SCR system 450 where the NOx gases are reduced by the catalyst 452.
  • the exhaust gas then enters the second oxidation catalyst assembly 460 in which the second sulfur catalyst 466 traps any remaining SOx gases in the exhaust gas.
  • Any ammonia exhaust gas in the exhaust gas e.g., produced by an exhaust reductant such as an aqueous urea solution inserted into the SCR system 450
  • the second oxidation catalyst assembly 460 can also serve as a backup SOx trap in case the first oxidation catalyst assembly 410 fails.
  • the first oxidation catalyst assembly 410 and/or the second oxidation catalyst assembly 460 can be replaced with the oxidation catalyst assembly 310, as described herein.
  • the first oxidation catalyst assembly 410 is excluded such that the aftertreatment system 400 only includes the second oxidation catalyst assembly 460 positioned downstream of the SCR system 450.
  • a filter e.g., the filter 120
  • a filter can also be positioned downstream of the SCR system 150 and upstream of the second oxidation catalyst assembly 460.
  • the filter positioned upstream and/or downstream of the SCR system 450 can be included in place of the first oxidation catalyst assembly 410 and/or the second oxidation catalyst assembly 460, respectively.
  • the singular forms "a”, “an” and “the” include plural referents unless the context clearly dictates otherwise.
  • the term “a member” is intended to mean a single member or a combination of members, "a material” is intended to mean one or more materials, or a combination thereof.
  • Coupled means the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members or the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional intermediate members being attached to one another.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Biomedical Technology (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Analytical Chemistry (AREA)
  • Materials Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • Exhaust Gas After Treatment (AREA)

Abstract

L'invention concerne un système de post-traitement comprenant un ensemble catalyseur d'oxydation définissant un canal à travers lequel coule un gaz d'échappement. Le canal comprend une entrée et une sortie. L'ensemble catalyseur d'oxydation comporte un substrat, un catalyseur d'oxydation et un catalyseur de soufre. Un système de réduction catalytique sélective (SCR selon l'abréviation anglo-saxonne) est positionné en aval de l'ensemble catalyseur d'oxydation. Le système SCR comporte au moins un catalyseur formulé de manière à réduire le gaz d'échappement. L'ensemble catalyseur d'oxydation peut être disposé en couches, le catalyseur d'oxydation étant ainsi étalé sur le substrat. En outre, le catalyseur de soufre est étalé sur le catalyseur d'oxydation, le catalyseur de soufre définissant ainsi le canal.
PCT/US2015/027741 2015-04-27 2015-04-27 Catalyseur d'oxydation bicouche destiné à améliorer le rendement de soufre WO2016175737A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/US2015/027741 WO2016175737A1 (fr) 2015-04-27 2015-04-27 Catalyseur d'oxydation bicouche destiné à améliorer le rendement de soufre

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2015/027741 WO2016175737A1 (fr) 2015-04-27 2015-04-27 Catalyseur d'oxydation bicouche destiné à améliorer le rendement de soufre

Publications (1)

Publication Number Publication Date
WO2016175737A1 true WO2016175737A1 (fr) 2016-11-03

Family

ID=57198566

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2015/027741 WO2016175737A1 (fr) 2015-04-27 2015-04-27 Catalyseur d'oxydation bicouche destiné à améliorer le rendement de soufre

Country Status (1)

Country Link
WO (1) WO2016175737A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5472673A (en) * 1992-08-04 1995-12-05 Toyota Jidosha Kabushiki Kaisha Exhaust gas purification device for an engine
US6272848B1 (en) * 1997-07-17 2001-08-14 Hitachi, Ltd. Exhaust gas cleaning apparatus and method for internal combustion engine
US6777370B2 (en) * 2001-04-13 2004-08-17 Engelhard Corporation SOx tolerant NOx trap catalysts and methods of making and using the same
US20070269353A1 (en) * 2003-11-04 2007-11-22 Engelhard Corporation Emission Treatment System with NSR and SCR Catalysts
EP1645325B1 (fr) * 2002-06-25 2011-12-14 Ford Global Technologies, LLC Piège à SOx pour véhicules à moteur Diesel et à mélange pauvre

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5472673A (en) * 1992-08-04 1995-12-05 Toyota Jidosha Kabushiki Kaisha Exhaust gas purification device for an engine
US6272848B1 (en) * 1997-07-17 2001-08-14 Hitachi, Ltd. Exhaust gas cleaning apparatus and method for internal combustion engine
US6777370B2 (en) * 2001-04-13 2004-08-17 Engelhard Corporation SOx tolerant NOx trap catalysts and methods of making and using the same
US6923945B2 (en) * 2001-04-13 2005-08-02 Engelhard Corporation Layered SOX tolerant NOX trap catalysts and methods of making and using the same
EP1645325B1 (fr) * 2002-06-25 2011-12-14 Ford Global Technologies, LLC Piège à SOx pour véhicules à moteur Diesel et à mélange pauvre
US20070269353A1 (en) * 2003-11-04 2007-11-22 Engelhard Corporation Emission Treatment System with NSR and SCR Catalysts

Similar Documents

Publication Publication Date Title
JP5676089B2 (ja) ディーゼル酸化触媒及びこれを具備した排気装置
US10989096B2 (en) Close coupled single module aftertreatment system
US7225613B2 (en) Diesel engine after treatment device for conversion of nitrogen oxide and particulate matter
KR101631149B1 (ko) 암모니아 분해 모듈을 가지는 디젤엔진 배기가스 배출장치
US8402754B2 (en) Apparatus for purifying exhaust gas
US8992869B2 (en) Ammonia oxidation catalyst system
RU2617770C2 (ru) Автомобильная система дополнительной каталитической обработки
JP6396636B2 (ja) 排気ガス制御の改善
US20100300078A1 (en) Exhaust After Treatment System
US10005031B2 (en) Dual-layer catalyst
JP2011052679A (ja) ディーゼルエンジンの排気ガス後処理装置
US20140134062A1 (en) Exhaust gas purification system of vehicle
EP2298432A1 (fr) Purificateur de gaz d'échappement
JP2011052610A (ja) 排気ガス浄化装置
JP2008075610A (ja) 排気処理装置
JP2009150279A (ja) 排気処理装置
JP2018145869A (ja) 排気ガス浄化システム、及び排気ガス浄化システムの硫黄被毒抑制方法
US10247070B2 (en) System and methods for reducing SOx gases in aftertreatment systems
JP4097362B2 (ja) 排出ガス浄化触媒及び排出ガス浄化装置
KR100916401B1 (ko) 입자상물질 및 질소산화물 정화장치
WO2016175737A1 (fr) Catalyseur d'oxydation bicouche destiné à améliorer le rendement de soufre
WO2017104668A1 (fr) Système de purification de gaz d'échappement de moteur à combustion interne et procédé de purification de gaz d'échappement de moteur à combustion interne
JP7389617B2 (ja) ディーゼルエンジン用排ガス浄化装置およびその用途
US20170082001A1 (en) Diesel engine exhaust gas treatment system with enhanced nitrogen oxide purification performance
KR20100008956A (ko) 디젤엔진 배기가스 배출장치

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15890880

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15890880

Country of ref document: EP

Kind code of ref document: A1