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: Catalysts and catalytic articles for treating exhaust gas streams are described. In one or more embodiments, a catalyst system includes a first zone to abate nitrogen oxides by selective catalytic reduction, a second zone to oxidize ammonia and a third zone to oxidize carbon monoxide and hydrocarbons. Methods for treating the exhaust gas stream are also provided. Methods of making and using such catalysts and catalytic articles are also described.

Abstract: Provided are emissions treatment systems for an exhaust stream having an ammonia-generating component, such as a NOx storage reduction (NSR) catalyst or a lean NOx trap (LNT) catalyst, and an SCR catalyst disposed downstream of the ammonia-generating catalyst. The SCR catalyst can be a molecular sieve having the CHA crystal structure, for example SSZ-13 or SAPO-34, which can be ion-exchanged with copper. The LNT can be layered, having an undercoat washcoat layer comprising a support material, at least one precious metal, and at least one NOx sorbent selected from the group consisting of alkaline earth elements, rare earth elements, and combinations thereof and a top washcoat layer comprising a support material, at least one precious metal, and ceria in particulate form, the top washcoat layer being substantially free of alkaline earth components. The emissions treatment system is advantageously used for the treatment of exhaust streams from diesel engines and lean burn gasoline engines.

Abstract: Provided are selective catalytic reduction catalytic articles, emission treatment systems and methods for simultaneously remediating the nitrogen oxides (NOx), particulate matter, and gaseous hydrocarbons present in diesel engine exhaust streams. The catalytic articles have a Selective Catalytic Reduction (SCR) catalyst uniformly coated over the outlet portion of wall flow filter walls resulting in reduction of NO2 and combustion of the soot without substantially increasing the system backpressure.

Abstract: Provided are catalyst articles, emission treatment systems and methods for simultaneously remediating the carbon monoxide, nitrogen oxides (NOx), particulate matter, and gaseous hydrocarbons present in diesel engine exhaust streams. The emission treatment system of specific embodiment effectively treats diesel engine exhaust with a single catalyst article.

Abstract: Catalytic articles, methods and emissions treatment systems for treating an engine exhaust gas stream containing NOx and particulate matter are disclosed and include a particulate filter comprising a first SCR catalyst for NOx conversion disposed downstream of the injector. The particulate filter is a partial filter with a particle filtration efficiency between about 30% and 60% and an SCR catalyst loading in the range of 0.1 g/in3-3.5 g/in3.

Abstract: Emissions treatment systems and methods for treating an engine exhaust gas stream containing NOx and particulate matter are disclosed including a particulate filter comprising a first SCR catalyst for NOx conversion a second SCR catalyst for NOx conversion on a substrate disposed downstream of the particulate filter. The system NOx conversion and the system back pressure increase lie within a targeted operational window.

Abstract: Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

Abstract: Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

Abstract: Provided are systems and/or methods that facilitate regeneration of a soot filter for a diesel engine. The systems and/or methods can include a bypass tube that connects a compressor side of a turbocharger to an exhaust side of the turbocharger. Compressed air from the turbocharger is introduced through the bypass tube into the soot filter and reduced a soot filter temperature, thereby mitigating the risk of thermal shock and over temperature conditions in the soot filter.

Abstract: An emission treatment system and associated method for treating an exhaust stream containing nitrogen oxides and particulate matter are disclosed. One embodiment of the system comprises a flow-through oxidation catalyst, a reductant injector downstream from the oxidation catalyst, a particulate filter downstream from the reductant injector, an SCR catalyst downstream from the particulate filter and an ammonia oxidation catalyst downstream from the SCR catalyst. An embodiment of the method comprises passing the exhaust gas stream through the oxidation catalyst, injecting a reductant into the exhaust gas stream, passing the exhaust gas stream through the particulate filter, passing the exhaust gas stream through an SCR catalyst, and passing the exhaust gas stream through an ammonia oxidation catalyst.

Abstract: Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.