Abstract: The invention relates to a composition essentially consisting of ceria-zirconia mixed oxide, with a ceria content of at least 60 wt. % and, after 4 hours of calcination at 1000° C., a specific surface area of at least 15 m2/g and a quantity of mobile oxygen between 200° C. and 400° C. of at least 0.7 ml 02/g. Said composition is produced using a method wherein a mixture of cerium and zirconium compounds is continuously reacted with a basic compound in a reactor, with a maximum residence time of the reactive medium in the mixture zone of the reactor of 100 milliseconds; and the precipitate is heated then brought into contact with a surfactant before being calcinated.

Abstract: System to reduce the amount of NOx in exhaust gases of a vehicle. The system includes a storage space 1 containing an agent, a SCR catalytic converter 5, an injection module 6c to inject the agent upstream of the converter, a heat exchanger 2 containing a porous matrix, a shutter or injector 11 to control the flow rate of the agent to the exchanger, a valve 12 between the storage space and exchanger, to transfer thermal energy to gases during the starting period. The shutter or injector controls the flow of agent into the exchanger during the starting period to raise its temperature, and is closed when gases have reached a certain temperature. The valve regulates exchanger pressure during a period at operating temperature and conveys the agent to storage space when the exchanger pressure is higher than storage space pressure.

Abstract: An exhaust gas control apparatus for an internal combustion engine includes: a NOx purification catalyst arranged in an exhaust passage of the internal combustion engine; a degradation degree estimating unit estimating a degradation degree of the NOx purification catalyst; and an air-fuel ratio control unit adjusting an air-fuel ratio of exhaust gas flowing into the NOx purification catalyst, wherein, until the estimated degradation degree of the NOx purification catalyst reaches a predetermined degradation degree, the air-fuel ratio control unit adjusts the air-fuel ratio of the exhaust gas to a rich air-fuel ratio, and, when the estimated degradation degree of the NOx purification catalyst exceeds the predetermined degradation degree, the air-fuel ratio control unit changes the air-fuel ratio of the exhaust gas from the rich air-fuel ratio to a lean air-fuel ratio so that the NOx purification catalyst is regenerated.

Abstract: Catalytic articles, systems and methods for treating exhaust gas streams are described. A catalytic article comprising a wall flow filter having gas permeable walls, a hydrolysis catalyst, an optional soot oxidation catalyst, a selective catalytic reduction catalyst permeating the walls, an ammonia oxidation catalyst and an oxidation catalyst to oxidize CO and hydrocarbons is described. Methods of treating exhaust gas streams comprising soot, an ammonia precursor such as urea, ammonia, NOx, CO and hydrocarbons are also provided.

Abstract: A method and apparatus are provided for reducing emissions of particulates from diesel engines. Exhaust is passed through a diesel particular filter having at least two stages comprised of (a) a catalyst section having a platinum group metal catalyst on contact surfaces within the catalyst section and (b) a filter section comprised of passages effective to remove particulates from a moving stream of combustion gases generated by combusting the fuel in the engine and holding them therein to permit their oxidation. Carbon removal is enhanced by utilizing levels of platinum group metal composition, cerium compositions, fuels and/or optional chemical enhancers to generate NO2 in the catalyst section in amounts sufficient to form cerium nitrates in the filter section. The cerium oxide is associated with and maintains dispersion of the platinum in the filter section, and the cerium nitrates are available at the surface and within the soot particles to provide enhanced soot oxidation at a lower balance point.

Abstract: A method of reducing nitrogen oxides (NOx) in a flowing combustion exhaust gas to N2, which method comprising oxidizing nitrogen monoxide to nitrogen dioxide on a transition metal/elite catalyst at catalyst bed temperatures below 50° C. and reducing NOx with the catalyst using an hydrocarbon (HC) reductant at catalyst bed temperatures below 150° C.

Abstract: Described is a selective catalytic reduction catalyst comprising an 8-ring small pore molecular sieve promoted with copper and an alkaline earth component. The catalyst is effective to catalyze the reduction of nitrogen oxides (NOx) in the presence of a reductant. A method for selectively reducing nitrogen oxides is also described.

Abstract: Provided are improved exhaust gas cleaning systems and methods for treating exhaust gas from a combustion source that include a hydrogen generation system, a regenerable sulfur oxides trap, and a regenerable nitrogen storage reduction (NSR) catalyst trap. The improved exhaust gas cleaning systems and methods allow for the sulfur released from the sulfur trap to pass through the nitrogen oxide trap with no or little poisoning of NOx storage and reduction sites, which significantly improves NSR catalyst trap lifetime and performance to meet future emissions standards. The disclosed exhaust gas cleaning systems are suitable for use in internal combustion engines (e.g., diesel, gasoline, CNG) which operate with lean air/fuel ratios over most of the operating period.

Abstract: The present invention pertains to catalyst systems for nitrogen oxide, carbon monoxide, hydrocarbon, and sulfur reactions that are free or substantially free of platinum group metals. The catalyst system of the present invention comprise a substrate and a washcoat, wherein the washcoat comprises at least one oxide solid, wherein the oxide solid comprises one or more selected from the group consisting of a carrier material oxide, a catalyst, and mixtures thereof. The catalyst system may optionally have an overcoat, wherein the overcoat comprises at least one oxide solid, wherein the oxide solid comprises one or more selected from the group consisting of a carrier material oxide, a catalyst, and mixtures thereof. The catalyst comprises one or more selected from the group consisting of a ZPGM transition metal catalyst, a mixed metal oxide catalyst, a zeolite catalysts, or mixtures thereof.

Abstract: Disclosed are, inter alia, methods of forming coated substrates for use in catalytic converters, as well as washcoat compositions and methods suitable for using in preparation of the coated substrates, and the coated substrates formed thereby. The catalytic material is prepared by a plasma-based method, yielding catalytic material with a lower tendency to migrate on support at high temperatures, and thus less prone to catalyst aging after prolonged use. Also disclosed are catalytic converters using the coated substrates, which have favorable properties as compared to catalytic converters using catalysts deposited on substrates using solution chemistry. Also disclosed are exhaust treatment systems, and vehicles, such as diesel vehicles, particularly light-duty diesel vehicles, using catalytic converters and exhaust treatment systems using the coated substrates.

Abstract: The present invention relates to a process for reducing cold start emissions in an exhaust gas stream by contacting the exhaust stream with a combination of molecular sieves comprising (1) a small pore crystalline molecular sieve or mixture of molecular sieves having pores no larger than 8 membered rings selected from the group consisting of SSZ-13, SSZ-16, SSZ-36, SSZ-39, SSZ-50, SSZ-52 and SSZ-73 and (2) a medium-large pore crystalline molecular sieve having pores at least as large as 10 membered rings selected from the group consisting of SSZ-26, SSZ-33, SSZ-64, zeolite Beta, CIT-1, CIT-6 and ITQ-4.

Abstract: A composition of zirconium oxide and at least one oxide of a rare earth other than cerium is described. The zirconium oxide has a weight proportion of at least 50% and, after calcination at a temperature of 900° C. for 4 hours, the composition exhibits two populations of pores of which their respective diameters are centered. The diameter of the first pore has a value of from 20 nm to 40 nm and in the second pore has a value of from 80 nm to 200 nm. Further described is how the composition can be used for treating the exhaust gases of internal combustion engines.

Abstract: Aspects of the invention relate to a method of treating a gas stream generated by a motorcycle, the method comprising: contacting a gas stream containing hydrocarbons, carbon monoxide and nitrogen oxides and generated by a motorcycle under both rich and lean engine operating conditions with a base metal catalyst composition, thereby removing at least a part of the hydrocarbons, carbon monoxide and nitrogen oxides in gas stream. The base metal catalyst composition comprises a support including at least 10% by weight of reducible ceria, and about 3 to about 7 wt % MnO and about 8 to about 22 wt % CuO on the reducible ceria support. The base metal catalyst composition is effective to promote a steam reforming reaction of hydrocarbons and a water gas shift reaction to provide H2 as a reductant to abate NOx.

Abstract: A three way catalyst includes an extruded solid body having by weight: 10-100% of at least one binder/matrix component; 5-90% of a zeolitic molecular sieve, a non-zeolitic molecular sieve or a mixture of any two or more thereof; and 0-80% optionally stabilised ceria. The catalyst also includes at least one precious metal and optionally at least one non-precious metal, wherein: (i) the at least one precious metal is carried in one or more coating layer(s) on the body surface; (ii) at least one metal is present throughout the body and at least one precious metal is carried in one or more coating layer(s) on a body surface; or (iii) at least one metal is present throughout the body, is present in a higher concentration at a body surface, and at least one precious metal is carried in one or more coating layer(s) on the body surface.

Abstract: Catalysts, catalytic articles, and catalyst systems and methods for treating exhaust gas streams utilizing the catalytic articles are described. In one or more embodiments, a catalytic article includes a first SCR catalyst permeating the porous walls of a substrate and a second SCR catalyst coating the walls of the substrate. Methods for treating an exhaust gas stream are also provided. Methods of making and using such catalysts and catalytic articles are also described.

Abstract: The invention relates to the use of aqueous guanidinium formiate solutions, optionally combined with urea and/or ammonia and/or ammonium salts, for the selective catalytic reduction of nitrogen oxides using ammonia in exhaust gases of vehicles. The inventive guanidinium formiate solutions enable a reduction of the nitrogen oxides by approximately 90%. Furthermore, said guanidinium formiate solutions can enable an increase in the ammonia forming potential from 0.2 kg, corresponding to prior art, up to 0.4 kg ammonia per liter of guanidinium formiate, along with freezing resistance (freezing point below ?25° C.). The risk of corrosion of the inventive guanidinium formiate solutions is also significantly reduced compared to that of solutions containing ammonium formiate.

Abstract: The invention provides an exhaust gas cleaning oxidation catalyst and in particular to an oxidation catalyst for cleaning the exhaust gas discharged from internal combustion engines of compression ignition type (particularly diesel engines). The invention further relates to a catalysed substrate monolith comprising an oxidizing catalyst on a substrate monolith for use in treating exhaust gas emitted from a lean-burn internal combustion engine. In particular, the invention relates to a catalysed substrate monolith comprising a first washcoat coating and a second washcoat coating, wherein the second washcoat coating is disposed in a layer above the first washcoat coating.

Abstract: A method for controlling a selective catalytic reduction system (SCR) exploiting a set of predetermined trigger events and a set point for the NOx concentration, and an arrangement for SCR. At the occurrence of a trigger event, NOx concentration measurement downstream from the catalyst elements is started and the difference between the measured concentration and the set point is determined. If the difference is negative, the dosing of the reducing agent is decreased. If the difference is positive, the dosing of the reducing agent is increased and after system stabilization a new measurement is started. If the measured value is below the previous measured value, the same dosing is maintained. If the measured value is above the previous measured value, the dosing is decreased with an amount greater than the increase after the previous measurement.

Abstract: The invention relates to a method for treating a gas containing nitrogen oxides (NOx), in which an NOx-reduction reaction is carried out using a nitrogen-containing reducing agent, which invention is characterized in that the catalyst used for the reduction reaction is a catalytic system containing a composition comprising zirconium, niobium in the following percentages by weight, expressed in terms of the weight of oxide: 10-50% of cerium, 5-20% of niobium and the remainder consisting of zirconium.

Abstract: The composition according to the invention is based on zirconium oxide, cerium oxide and at least one oxide of a rare earth other than cerium, in a proportion, by weight, of zirconium oxide of at least 5% and of cerium oxide of at most 90%, and it is characterized in that it additionally comprises silicon oxide in an amount, by weight, of between 0.1% and 2%. This composition may be used in catalysis, in particular in systems for treating the exhaust gases of internal combustion engines.

Abstract: Disclosed embodiments include methods of removing carbon dioxide from combustion gas from an engine of a vehicle, systems for removing carbon dioxide from combustion gas from an engine of a vehicle, vehicles, methods of managing carbon dioxide emissions from an engine of a vehicle, and computer software program products for managing carbon dioxide emissions from an engine of a vehicle.

Abstract: Provided is a catalyst for purifying an exhaust gas, the catalyst excelling in catalytic performance and oxygen storage capacity. The catalyst for purifying an exhaust gas is a catalyst for purifying an exhaust gas which includes a ceria-zirconia composite oxide having a pyrochlore structure and a ceria-zirconia composite oxide having a cubic crystal structure, wherein at least a part of the ceria-zirconia composite oxide is composited with the ceria-zirconia composite oxide.

Abstract: A NOx absorber catalyst comprising an extruded solid body comprises either: (A) 10-95% by weight of at least one binder/matrix component; and 5-90% by weight of a zeolitic molecular sieve, a non-zeolitic molecular sieve or a mixture of any two or more thereof, which catalyst comprising at least one metal comprising (a) at least one precious metal; and (b) at least one alkali metal or at least one alkaline earth metal, wherein (a) and (b) are carried in one or more coating layer(s) on a surface of the extruded solid body; or (B) 10-95% by weight of at least one binder/matrix component; and 5-80% by weight optionally stabilized ceria, which catalyst comprising at least one metal comprising (a) at least one precious metal; and (b) at least one alkali metal or at least one alkaline earth metal.

Abstract: A method of making composite nanoscale particles comprising subjecting a starting material to laser energy so as to form a vapor and condensing the vapor so as to form the composite nanoscale particles, wherein said composite nanoscale particles comprise a first metal and/or a first metal oxide incorporated in nanoscale particles of an oxide of a second metal, the first metal being different than the second metal. The starting material can comprise first and second metals or compounds of the first and second metals. The composite nanoscale particles can be formed in a reaction chamber wherein a temperature gradient is provided. The atmosphere in the chamber can be an inert atmosphere comprising argon or a reactive atmosphere comprising oxygen. The composite nanoscale particles are useful for low-temperature and near-ambient temperature catalysis.

Abstract: The present invention is an exhaust gas purification catalyst equipment, and a method of use thereof, formed by arranging a selective catalytic reduction type catalyst for purifying nitrogen oxides in exhaust gas exhausted from lean combustion engines using ammonia or urea as a reducing agent, it is provided with a selective catalytic reduction type catalyst, characterized in that said catalyst comprises a lower-layer catalyst layer (A) having an oxidative function for nitrogen monoxide (NO) in exhaust gas and an upper-layer catalyst layer (B) having an adsorbing function for ammonia on the surface of a monolithic structure type carrier (C), and that the lower-layer catalyst layer (A) comprises a noble metal component (i), an inorganic base material constituent (ii) and zeolite (iii), and the upper-layer catalyst layer (B) comprises substantially none of component (i) but the component (iii), in a flow path of exhaust gas, characterized in that a spraying means to supply an urea aqueous solution or an aqueous

Abstract: An exhaust purification device and an exhaust purification method that utilizes this exhaust purification device enable effective utilization of exhaust gas heat and allow reduction in the size of the device. The exhaust purification device has an oxidation catalyst that is disposed in an exhaust passage of a diesel engine and purifies CO and HC in exhaust gas; a urea injection nozzle that is disposed downstream of the oxidation catalyst and generates ammonia through atomization of urea water into the exhaust gas; a turbine of a turbocharger, this turbine being disposed downstream of the urea injection nozzle and accelerating decomposition of urea through agitation of the atomized urea water; a DPF that is disposed downstream of the turbine and traps PM in the exhaust gas; and a selective reduction catalyst that is disposed downstream of the DPF and detoxifies NOx in the exhaust gas through a reduction reaction with ammonia.

Abstract: System and methods for reducing secondary emissions in an exhaust stream from an internal combustion engine are disclosed. The systems and methods include a filtration device positioned downstream from an SCR catalyst of an aftertreatment system disposed in the exhaust system. The filtration device can also be used for particulate filter diagnostics and for treatment of ammonia slip.

Abstract: A system and method according to which exhaust is directed from a stationary exhaust source and through a burner, and a combustible fluid is vented from at least one combustible fluid source other than the stationary exhaust source. The combustible fluid is captured and directed to flow from the combustible fluid source and towards the burner, and at least air is mixed with the captured combustible fluid to form a mixture. The mixture is introduced into the burner and burned therein to thereby pre-heat the exhaust flowing therethrough. The pre-heated exhaust contacts a catalyst.

Abstract: A method of using a hybrid oxidation catalyst system for remediating a lean emission from a vehicle includes the step of oxidizing the hydrocarbons and carbon monoxide in an engine emission comprising hydrocarbons, carbon monoxide, NOx including NO and NO2, and oxygen with a first catalyst. The first catalyst includes noble metal particles supported in a first ceramic layer. The method further includes oxidizing the NO with a second catalyst having base metal oxide particles supported in a second ceramic layer to form NO2. The first catalyst is disposed upstream of the second catalyst and the system is capable of converting at least 10% of the amount of NO to NO2 at a temperature ranging from 75° C. to 225° C.

Abstract: A method of assessing overall efficiency of a selective-catalytic-reduction catalyst includes monitoring instantaneous efficiency of the catalyst. The method also includes determining the overall efficiency by summing instantaneous efficiency values weighted by a first set of coefficients if the most recent instantaneous efficiency value is above an instantaneous efficiency threshold. The method additionally includes determining the overall efficiency by summing instantaneous efficiency values weighted by a second set of coefficients if the most recent instantaneous efficiency value is equal to or below the instantaneous efficiency threshold. Furthermore, the method includes determining whether the overall efficiency has dropped below an overall efficiency threshold and reporting when the overall efficiency has dropped below the overall efficiency threshold.

Abstract: To provide an oxidation catalyst capable of burning PM of diesel engine exhausts gas at a low temperature, and hardly subjected to poisoning due to sulfur oxide. A composite oxide contains Ce, Bi, and M (wherein M is one or more elements selected from Mg, Ca, Sr, and Ba) and oxygen, and is manufactured, with a molar ratio of Ce, Bi, M expressed by Ce:Bi:M=(1?x?y):x:y, satisfying 0<x?0.4, and 0<y?0.4. This composite oxide is suitable as a PM combustion catalyst, and is hardly subjected to poisoning due to sulfur oxide.

Abstract: A method for use with an exhaust gas post-treatment system on an internal combustion engine operated with air surplus includes reducing nitrous oxides in that an ammonia-separating reducing agent is added to the exhaust gas flow upstream of a catalyst which is charged with a catalyst material for selective catalytic reduction of nitrous oxides. The method further provides that the NH3 to NOx ratio (feed ratio ?) is varied in phases by changing the untreated nitrous oxide emissions of the internal combustion engine such that the feed ratio ? oscillates in phases about a predefined value.

Abstract: The present disclosure relates to a method for controlling an injection device for feeding an ammonia-releasing reducing agent into an exhaust-gas purification system of an internal combustion engine for the purpose of reducing the nitrogen oxide emissions, wherein the exhaust-gas purification system comprises at least one SCR catalytic converter with n cells which are arranged in series in the exhaust-gas throughflow direction and in which ammonia can be stored.

Abstract: Provided is a particulate combustion catalyst including a carrier formed of monoclinic zirconium oxide particles, and metallic Ag or Ag oxide, which serves as a catalyst component and is supported on the carrier, wherein the amount of the catalyst component is 0.5 to 10 mass %, as reduced to metallic Ag, on the basis of the mass of the carrier, and preferably, the catalyst has a BET specific surface area of 8 to 21 m2/g. Also provided are a particulate filter coated with the particulate combustion catalyst; and an exhaust gas cleaning apparatus including a particulate filter coated with the particulate combustion catalyst.

Abstract: The invention relates to the use of mixed oxides made of cerium oxide, zirconium oxide, rare earth sesquioxide and niobium oxide as catalytically active materials for the selective catalytic reduction of nitrogen oxides with ammonia or a compound that can decompose to form ammonia in the exhaust gas of internal combustion engines in motor vehicles that are predominantly leanly operated, and to compositions or catalysts which contain said mixed oxides in combination with zeolite compounds and/or zeolite-like compounds and are suitable for the denitrogenation of lean motor vehicle exhaust gases in all essential operating states.

Abstract: Provided are exhaust systems and components suitable for use in conjunction with gasoline engines to treat gaseous emissions such as hydrocarbons, nitrogen oxides, and carbon monoxides. Layered three-way conversion (TWC) catalysts comprise an outer layer whose rhodium is supported by an oxygen storage component, such as a ceria-zirconia composite, and the outer layer is substantially free from alumina as a support. The rhodium-containing layer can be free of all other precious metals, such as platinum and palladium. A lower palladium layer is provided where the palladium is supported by a refractory metal oxide. The lower palladium layer can be free of rhodium and platinum and can contain an oxygen storage component that is the same or different from that in the rhodium-containing layer. Methods of making and using these catalysts are also provided.

Abstract: An exhaust gas treatment system for an internal combustion engine to control desulfurization of at least one aftertreatment device is provided. The exhaust gas treatment system includes a desulfurization mode trigger module, a desulfurization control module, and an interrupt module. The desulfurization mode trigger module is configured to set a desulfurization request based on one or more trigger conditions. The desulfurization control module is configured to control desulfurization of at least one aftertreatment device based on the desulfurization request. The interrupt module is configured to interrupt the desulfurization of at least one aftertreatment device based on an interrupt condition.

Abstract: Systems and methods are disclosed that include an exhaust gas stream produced by an engine and an aftertreatment system including an SCR catalyst element receiving at least a portion of the exhaust gas stream. An exhaust outlet flow path has an inlet fluidly coupled to the exhaust gas stream at a position downstream of at least a portion of the SCR catalyst element that bypasses at least a portion of exhaust gas stream to provide for compositional measurement of the exhaust gas with a compositional sensor located downstream of a diagnostic catalyst positioned in the exhaust outlet flow path.

Abstract: The present invention relates to a catalytic composition comprising a noble metal on an acidic tungsten-containing mixed oxide, a method for producing the catalytic composition and the use of the catalytic composition as oxidation catalyst. The invention further relates to a catalyst shaped body, which has the catalytic composition on a support, a washcoat containing the catalytic composition according to the invention and the use of the washcoat to produce a coated catalyst shaped body.

Abstract: A catalyst for the selective catalytic reduction of nitrogen oxides in diesel engine exhaust gases using ammonia or a precursor compound decomposable to ammonia is described. The catalyst comprises two superposed coatings applied to a support body, of which the first coating applied directly to the support body comprises a transition metal-exchanged zeolite and/or a transition metal-exchanged zeolite-like compound, and effectively catalyzes the SCR reaction. The second coating has been applied to the first coating so as to cover it on the exhaust gas side. It is configured so as to prevent the contact of hydrocarbons having at least three carbon atoms present in the exhaust gas with the layer beneath, without blocking the passage of nitrogen oxides and ammonia to the first coating.

Abstract: A wall-flow filter comprises a catalyst for converting oxides of nitrogen in the presence of a reducing agent, which wall-flow filter comprising an extruded solid body comprising: 10-95% by weight of at least one binder/matrix component; 5-90% by weight of a zeolitic molecular sieve, a non-zeolitic molecular sieve or a mixture of any two or more thereof; and 0-80% by weight optionally stabilized ceria, which catalyst comprising at least one metal, wherein: the at least one metal is present throughout the extruded solid body alone or in combination with: is also present in a higher concentration at a surface of the extruded solid body; is also carried in one or more coating layer(s) on a surface of the extruded solid body; or both.

Abstract: A filter for filtering particulate matter (PM) from exhaust gas emitted from a positive ignition engine or a compression ignition engine, which filter comprising a porous substrate having inlet surfaces and outlet surfaces, wherein the inlet surfaces are separated from the outlet surfaces by a porous structure containing pores of a first mean pore size, wherein the porous substrate is coated with a washcoat comprising a plurality of solid particles wherein the porous structure of the washcoated porous substrate contains pores of a second mean pore size, and wherein the second mean pore size is less than the first mean pore size.

Abstract: A three way catalyst includes an extruded solid body having: 10-95% by weight of at least one binder/matrix component; 5-90% by weight of a zeolitic molecular sieve; and 0-80% by weight optionally stabilized ceria. The catalyst further includes at least one precious metal and optionally at least one non-precious metal. The at least one precious metal is carried in a coating layer on a surface of the extruded solid body; at least one metal is present throughout the extruded solid body and at least one precious metal is also carried in a coating layer on a surface of the extruded solid body; or at least one metal is present throughout the extruded solid body, is present in a higher concentration at a surface of the extruded solid body and at least one precious metal is also carried in a coating layer on the surface of the extruded solid body.

Abstract: An automobile exhaust gas catalytic converter includes a first catalyst layer; a second catalyst layer located on a downstream side as compared to the first catalyst layer; and a base material on which the first catalyst layer and the second catalyst layer are respectively located. In the exhaust gas catalytic converter, the proportion (LB/LS) of a coating length (LB) of the second catalyst layer from a downstream end of the base material with respect to a total length (LS) of the base material in the exhaust gas flow direction is approximately 50 to 90%, the proportion of an amount of Rh contained in the second catalyst layer with respect to a total amount of Rh contained in the first catalyst layer and the second catalyst layer is approximately 50 to 90% by mass, and the rest of Rh is contained together with Pd or Pt in the first catalyst layer.

Abstract: Aspects of the invention relate to a method of treating a gas stream generated by a motorcycle, the method comprising: contacting a gas stream containing hydrocarbons, carbon monoxide and nitrogen oxides and generated by a motorcycle under both rich and lean engine operating conditions with a base metal catalyst composition, thereby removing at least a part of the hydrocarbons, carbon monoxide and nitrogen oxides in gas stream. The base metal catalyst composition comprises a support including at least 10% by weight of reducible ceria, and about 3 to about 7 wt % MnO and about 8 to about 22 wt % CuO on the reducible ceria support. The base metal catalyst composition is effective to promote a steam reforming reaction of hydrocarbons and a water gas shift reaction to provide H2 as a reductant to abate NOx.

Abstract: A method of using a catalyst comprises exposing a catalyst to at least one reactant in a chemical process. The catalyst comprises copper and a small pore molecular sieve having a maximum ring size of eight tetrahedral atoms. The chemical process undergoes at least one period of exposure to a reducing atmosphere. The catalyst has an initial activity and the catalyst has a final activity after the at least one period of exposure to the reducing atmosphere. The final activity is within 30% of the initial activity at a temperature between 200 and 500° C.

Abstract: The present invention relates to the use, for the reduction of oxidizing contaminating entities of the NOx type, in particular NO2, present in a gas to be purified, of a catalytic system comprising or composed of an oxide corresponding to the molar formulation: Ce1-y-zO2-xMyNz, in which: Ce is cerium, M is an element chosen from: Gd, Y, Sc, Sm, La, Pr, Nd, Er or Tb, y is between 0.01 and 0.4, N is an element having several degrees of valency chosen from: Ti, V, Cr, Mn, Fe, Co, Ni or Cu, z is less than 0.4, x is greater than 0.05.

Abstract: A NOx selective reduction catalyst for reducing NOx by the ammonia adsorbed is disposed in an engine exhaust gas passage. As states of adsorption of ammonia by the catalyst, there are a first adsorption state of ammonia that occurs when the ammonia is adsorbed during low temperature and a second adsorption state of ammonia that occurs when the ammonia is adsorbed or has already been adsorbed during high temperature. The amount of adsorbed ammonia in the first state is restricted to control concentration of the ammonia that is in the first state and desorbed when the temperature of the catalyst increases so as to be not higher than an allowable concentration, and that in the second state is restricted to control concentration of the ammonia that is in the second state and desorbed when the temperature of the catalyst increases so as to be not higher than an allowable concentration.

Abstract: A catalyst system and a method for reducing nitrogen oxides in an exhaust gas by reduction with a hydrocarbon or oxygen-containing organic compound reducing agent are provided. The catalyst system contains a silver catalyst and a modifier catalyst, where the modifier catalyst contains a modifier oxide, where the modifier oxide is selected from the group consisting of iron oxide, cerium oxide, copper oxide, manganese oxide, chromium oxide, a lanthanide oxide, an actinide oxide, molybdenum oxide, tin oxide, indium oxide, rhenium oxide, tantalum oxide, osmium oxide, barium oxide, calcium oxide, strontium oxide, potassium oxide, vanadium oxide, nickel oxide, tungsten oxide, and mixtures thereof. The modifier oxide is supported on an inorganic oxide support or supports, where at least one of the inorganic oxide supports is an acidic support. The catalyst system of the silver catalyst and the modifier catalyst provides higher NOx conversion than either the silver catalyst or the modifier catalyst alone.

Abstract: Ag/Al2O3 materials may be packaged in a suitable flow-through reactor, in combination with another material selected as a passive NOx adsorber material (PNA), both the silver material and the adsorber material being close coupled to the exhaust manifold of a diesel engine, and upstream of other catalytic devices, such as a diesel oxidation catalyst and a selective reduction catalyst for NOx. The silver catalyst material uses hydrogen in a cold-start engine exhaust and serves to oxidize NO to NO2 in the relatively low temperature, hydrocarbon-containing, exhaust during a short period following the engine cold start, and to temporarily store NOx during the start-up period. After the flowing exhaust gas stream has heated the PNA and the downstream catalytic devices, the silver yields its nitrogen oxides for conversion to nitrogen by the then-operating devices before NOx is discharged to the atmosphere.