A catalytic converter system having oxygen storage materials is disclosed and methods for determining whether to reactivate oxygen storage materials and monitoring failure events of the oxygen storage materials are also disclosed.

An oxidation catalyst for treating an exhaust gas produced by a diesel engine comprises a catalytic region and a substrate, wherein the catalytic region comprises a catalytic material comprising: bismuth (Bi) or an oxide thereof; a Group 8 metal or an oxide thereof; a platinum group metal (PGM) selected from the group consisting of (i) platinum (Pt), (ii) palladium (Pd) and (iii) platinum (Pt) and palladium (Pd); and a support material, which comprises alumina, silica, a mixed oxide of alumina and a refractory oxide, a mixed oxide of silica and a refractory oxide, a composite oxide of alumina and a refractory oxide, a composite oxide of silica and a refractory oxide, alumina doped with a refractory oxide or silica doped with a refractory oxide.

A three-way catalyst article, and its use in an exhaust system for compressed natural gas engines, is disclosed. The catalyst article for treating exhaust gas from compressed natural gas (CNG) engine comprising: a substrate comprising an inlet end, an outlet end with an axial length L; a first catalytic region beginning at the outlet end and extending for less than the axial length L, wherein the first catalytic region comprises a first zeolite; and a second catalytic region beginning at the inlet end, wherein the second catalytic region comprises a second platinum group metal (PGM) component, a second oxygen storage capacity (OSC) material, and a second inorganic oxide; wherein the second PGM component is selected from the group consisting of palladium, platinum, rhodium or a combination thereof.

A layered diesel oxidation catalyst for treatment of exhaust gas emissions from a diesel engine comprising: a flow-through monolith substrate having a honeycomb structure and comprising a front zone and a rear zone, wherein the front zone of the substrate comprises a combination of layers, one on top of another and comprising two or more of layers A, B and C; and the rear zone comprises Layer D, wherein: Layer A comprises platinum, palladium, or combinations thereof on a molecular sieve; Layer B comprises 1) platinum, palladium, or combinations thereof on a refractory metal oxide support; and 2) an alkaline earth metal, preferably barium, strontium or combinations thereof; Layer C comprises 1) a platinum group metal, which is platinum or a combination of both platinum and palladium on a refractory metal oxide support; and 2) a promoter metal, which is manganese and/or bismuth; and layer D comprises 1) platinum or a combination of both platinum and palladium on a refractory metal oxide support; and 2) manganese (Mn).

The present invention relates to a catalyst for the oxidation of NO, for the oxidation of ammonia and for the selective catalytic reduction of NOx, comprising a substrate, a first coating comprising one or more of a vanadium oxide and a zeolitic material comprising one or more of copper and iron; and a second coating comprising a platinum group metal component supported on a non-zeolitic oxidic material, wherein the second coating further comprises a zeolitic material comprising one or more of copper and iron.

The presently invention provides an emission control catalyst article comprising a substrate, a bottom washcoat layer comprising a platinum group metal coated on the 60 to 100% length of the substrate, and a top washcoat layer comprising a platinum group metal coated on the 60 to 100% length of the substrate such that the top coat covers at least 60% of the length of the bottom washcoat layer, wherein at least a portion of the top washcoat layer, the bottom washcoat layer or both washcoat layers comprises a platinum group metal deposited within the said washcoat layer(s) with a platinum group metal gradient such that the PGM concentration in a top-most portion of the said washcoat layer is at least two time higher compared to the PGM concentration in a bottom-most portion of the said washcoat layer.

The present invention relates to a catalyst comprising two layers on an inert catalyst carrier, wherein a layer A lying directly on the catalyst carrier contains at least one platinum group metal and one cerium/zirconium/SE mixed oxide, and a layer B, applied on layer A and in direct contact with the flow of exhaust gas, contains at least one platinum group metal and a cerium/zirconium/SE mixed oxide, wherein SE stands for a rare earth metal other than from cerium, characterized in that the fraction of SE oxide in the cerium/zirconium/SE mixed oxide of layer A is less than the fraction of SE oxide in the cerium/zirconium/SE mixed oxide of layer B.

An ammonia adsorption catalyst and a preparation method and a use thereof, where the ammonia adsorption catalyst includes a substrate and an adsorption layer located on the surface of the substrate, and the adsorption layer includes a noble metal-containing zeolite adsorption material. The catalyst has the advantages of high ammonia adsorption/conversion efficiency, low cost, and flexible application, etc.

A nitrous oxide (N.sub.2O) removal catalyst composite is provided, comprising a N.sub.2O removal catalytic material on a substrate, the catalytic material comprising a rhodium (Rh) component supported on a ceria-based support, wherein the catalyst composite has a H.sub.2-consumption peak of about 100° C. or less as measured by hydrogen temperature-programmed reduction (H.sub.2-TPR). Methods of making and using the same are also provided.

An improved SCRoF (selective catalytic reduction on filter) device for treating exhaust from an internal combustion engine. The filter has numerous entry and exit channels. Exhaust enters the entry channels and flows through side walls into the exit channels. Relative to the exhaust flow path, these side walls are coated on the downstream side with a ceria-based catalyst and on the upstream side with a Cu-zeolite catalyst. This allows the filter to optimally achieve both particulate matter oxidation and NOx reduction, respectively.