摘要:
Diesel oxidation catalysts comprising a first washcoat layer including a platinum group metal impregnated on a promoted non-zeolitic support are described. The promoter is one or more of tin, manganese, indium, group VIII metals. Methods of making and using the diesel oxidation catalyst, including emissions treatment systems, are also described.
摘要:
Diesel oxidation catalysts comprising a first washcoat layer including a platinum group metal impregnated on a promoted non-zeolitic support are described. The promoter is one or more of tin, manganese, indium, group VIII metals. Methods of making and using the diesel oxidation catalyst, including emissions treatment systems, are also described.
摘要:
Provided is a catalyst composition, in particular a diesel oxidation catalyst, for the treatment of exhaust gas emissions, such as the oxidation of unburned hydrocarbons (HC), and carbon monoxide (CO). More particularly, the present invention is directed to a catalyst structure comprising at least two, specifically three distinct layers, at least one of which contains an oxygen storage component (OSC) that is present in a layer separate from the majority of the platinum group metal (PGM) components, such as palladium and platinum.
摘要:
Provided is a catalyst composition, in particular a diesel oxidation catalyst, for the treatment of exhaust gas emissions, such as the oxidation of unburned hydrocarbons (HC), and carbon monoxide (CO). More particularly, the present invention is directed to a catalyst structure comprising at least two, specifically three distinct layers, at least one of which contains an oxygen storage component (OSC) that is present in a layer separate from the majority of the platinum group metal (PGM) components, such as palladium and platinum.
摘要:
Provided are diesel exhaust components where palladium is segregated from a molecular sieve, specifically a zeolite, in a catalytic material. In the catalytic material, therefore, there are at least two layers: a palladium-containing layer that is substantially free of a molecular sieve and a hydrocarbon trap layer that comprises at least one molecular sieve and is substantially free of palladium. The palladium is provided on a high surface area, porous refractory metal oxide support. The catalytic material can further comprise a platinum component, where a minor amount of the platinum component is in the hydrocarbon trap layer, and a majority amount of the platinum component is in the palladium-containing layer. Systems and methods of using the same are also provided.
摘要:
Oxidation catalyst composites for the treatment of exhaust gas emissions, such as the abatement of unburned hydrocarbons (HC), and carbon monoxide (CO) and the oxidation of NO to NO2 are disclosed The catalyst composites comprise two washcoat layers containing two different compositions of platinum group metals to optimize the NO2 exiting the catalyst composite. The key to improvement in NO oxidation is to have one catalyst layer that contains Pt while being substantially free of Pd. Methods and systems utilizing the catalyst composites are also disclosed.
摘要:
Catalysts, methods, and systems for treating diesel engine exhaust streams are described. In one or more embodiments, the catalyst comprises platinum, a second metal from one of the groups VB, VIIB, VIIB, VIIIB, IB, or IIB of the periodic table, a refractory metal oxide, and a zeolite, the oxidation catalyst already being effective to remove ammonia at temperatures less than about 300° C. and exhibiting no significant decrease in ammonia oxidation efficiency upon hydrothermal aging. A method aspect includes first passing a vehicle's engine exhaust stream through a NOx abatement catalyst; and passing the exhaust stream exiting the NOx abatement catalyst and containing ammonia through the ammonia oxidation catalyst. Systems including such catalysts are also provided.
摘要:
Systems and methods for abating NOx in an exhaust stream are provided. System using a lean NOx trap, an air injector and optional catalysts and filters are described. The emissions treatment system is advantageously used for the treatment of exhaust streams from diesel engines and lean burn gasoline engines.
摘要:
Provided are diesel exhaust components where palladium is segregated from a molecular sieve, specifically a zeolite, in a catalytic material. In the catalytic material, therefore, there are at least two layers: a palladium-containing layer that is substantially free of a molecular sieve and a hydrocarbon trap layer that comprises at least one molecular sieve and is substantially free of palladium. The palladium is provided on a high surface area, porous refractory metal oxide support. The catalytic material can further comprise a platinum component, where a minor amount of the platinum component is in the hydrocarbon trap layer, and a majority amount of the platinum component is in the palladium-containing layer. Systems and methods of using the same are also provided.
摘要:
Diesel oxidation catalysts, catalytic articles, methods of making catalytic articles, emissions treatment systems and methods of treating an exhaust gas stream using the catalytic articles for the treatment of exhaust gas emissions, such as the oxidation of unburned hydrocarbons (HC) and carbon monoxide(CO) are described. Specific catalytic articles comprising a substrate with a first washcoat layer comprising greater than or equal to about 2% by weight palladium dispersed on a cerin support and a second washcoat layer comprising a platinum group metal and a refractory metal oxide are described.