Abstract: The present invention relates to a SCR catalytic article, comprising —a substrate and —a copper-containing small pore zeolite, having a crystal structure characterized by a decrease of unit cell volume upon sulfurization and desulfurization of less than ?3 as determined by an X-ray powder diffraction, wherein the sulfurization and desulfurization are carried out in accordance with the processes as described in the specification, and to an exhaust treatment system comprising the same. The present invention also relates to a method for determining whether a metal-promoted small pore zeolite is resistant to irreversible sulfur poisoning and a method for evaluating whether a metal-promoted small pore zeolite is qualified for resistance to irreversible sulfur poisoning.

Abstract: The present invention provides a method for treating a used particulate filter, comprising: removing particulates from the particulate filter; and introducing simulated ash into inlet channels of the particulate filter after removing the particulates.

Abstract: A catalyst article is provided including a substrate including a plurality of passageways, and further including a first and a second oxidation region including a first and a second subset of said plurality of passageways. A first catalyst composition is coating at least a portion of each passageway of the first oxidation region and positioned as a sole PGM-containing catalyst layer, or a zoned portion thereof, or as a top PGM-containing catalyst layer, or a zoned portion thereof, in the first oxidation region. A second catalyst composition is coating at least a portion of each passageway of the second oxidation region and positioned as a sole PGM-containing catalyst layer, or a zoned portion thereof, or as a top PGM-containing catalyst layer, or a zoned portion thereof, in the second oxidation region. The Pt:Pd weight ratio is greater in the first catalyst composition than in the second catalyst composition.

Abstract: The present invention relates to a particulate filter, in particular a particulate filter for use in an emission treatment system of an internal combustion engine. The particulate filter provides an advantageous combination of low back pressure and high fresh filtration efficiency.

Abstract: A catalyst article is provided including a substrate including a plurality of passageways, and further including a first and a second oxidation region including a first and a second subset of said plurality of passageways. A first catalyst composition is coating at least a portion of each passageway of the first oxidation region and positioned as a sole PGM-containing catalyst layer, or a zoned portion thereof, or as a top PGM-containing catalyst layer, or a zoned portion thereof, in the first oxidation region. A second catalyst composition is coating at least a portion of each passageway of the second oxidation region and positioned as a sole PGM-containing catalyst layer, or a zoned portion thereof, or as a top PGM-containing catalyst layer, or a zoned portion thereof, in the second oxidation region. The Pt:Pd weight ratio is greater in the first catalyst composition than in the second catalyst composition.

Abstract: The present invention relates to a catalyzed particulate filter and methods comprising the filter for treatment of an exhaust gas from a gasoline engine, the catalyzed particulate filter comprising a gasoline particulate filter (GPF); a major catalytic layer coated onto or within an inlet side, an outlet side, or both sides of the GPF surfaces, the major catalytic layer comprising a first composition, wherein the first composition comprising a first support material; and a first platinum group metal (PGM); and a minor functional material layer placed onto or within an inlet side, an outlet side, or both sides of the GPF surfaces; the minor catalytic layer comprising a second composition; wherein the major catalytic layer has a higher loading than the minor functional material layer; the minor functional material layer is placed on top of the major catalytic layer, or the major catalytic material layer is placed on top of the minor functional layer.

Abstract: A catalyst for gasoline engine exhaust gas after-treatment, comprising Pt and optionally at least one other platinum group metal on a hydrothermal stable support material which is coated onto a gasoline particulate filter. The catalyst oxidizes particulate matter trapped in the gasoline particulate filter under low temperature and abates NOx, CO and HC. Also a process for preparing the catalyst is disclosed, and a method for after-treatment of gasoline engine exhaust gas using the catalyst is disclosed.

Abstract: The present invention provides methods for low temperature desulfating sulfur-poisoned SCR catalysts, and emission control systems adapted to apply such desulfating methods, in order to regenerate catalytic NOx conversion activity. The methods are adapted for treating an SCR catalyst to desorb sulfur from the surface of the SCR catalyst and increase NOx conversion activity of the SCR catalyst, the treating step including treating the SCR catalyst with a gaseous stream comprising a reductant for a first treatment time period and at a first treatment temperature, wherein the first treatment temperature is about 350° C. or less, followed by a second treatment time period and a second treatment temperature higher than the first treatment temperature, wherein the molar ratio of reductant to NOx during the treating step is about 1.05:1 or higher.

Abstract: A catalyst for gasoline engine exhaust gas after-treatment, comprising Pt and optionally at least one other platinum group metal on a hydrothermal stable support material which is coated onto a gasoline particulate filter. The catalyst oxidizes particulate matter trapped in the gasoline particulate filter under low temperature and abates NOx, CO and HC. Also a process for preparing the catalyst is disclosed, and a method for after-treatment of gasoline engine exhaust gas using the catalyst is disclosed.

Abstract: Described are SCR catalyst systems comprising a first SCR catalyst composition and a second SCR catalyst composition arranged in the system, the first SCR catalyst composition promoting higher N2 formation and lower N2O formation than the second SCR catalyst composition, and the second SCR catalyst composition having a different composition than the first SCR catalyst composition, the second SCR catalyst composition promoting lower N2 formation and higher N2O formation than the first SCR catalyst composition. The SCR catalyst systems are useful in methods and systems to catalyze the reduction of nitrogen oxides in the presence of a reductant.

Abstract: The present invention provides methods for low temperature desulfating sulfur-poisoned SCR catalysts, and emission control systems adapted to apply such desulfating methods, in order to regenerate catalytic NOx conversion activity. The methods are adapted for treating an SCR catalyst to desorb sulfur from the surface of the SCR catalyst and increase NOx conversion activity of the SCR catalyst, the treating step including treating the SCR catalyst with a gaseous stream comprising a reductant for a first treatment time period and at a first treatment temperature, wherein the first treatment temperature is about 350° C. or less, followed by a second treatment time period and a second treatment temperature higher than the first treatment temperature, wherein the molar ratio of reductant to NOx during the treating step is about 1.05:1 or higher.

Abstract: Provided are catalyst articles, methods and systems for treating lean burn engine exhaust. Catalyst articles include selective catalytic reduction catalyst on a particulate filter. The SCR catalyst on the particulate filter provides limited NOx conversion so that unconverted NO2 is available to facilitate passive oxidation of soot trapped on the particulate filter by reaction with NO2. Systems and methods utilize such catalytic articles, and further include, e.g., a downstream selective catalytic reduction catalyst on a flow through substrate.

Abstract: Described are SCR catalyst systems comprising a first SCR catalyst composition and a second SCR catalyst composition arranged in the system, the first SCR catalyst composition promoting higher N2 formation and lower N2O formation than the second SCR catalyst composition, and the second SCR catalyst composition having a different composition than the first SCR catalyst composition, the second SCR catalyst composition promoting lower N2 formation and higher N2O formation than the first SCR catalyst composition. The SCR catalyst systems are useful in methods and systems to catalyze the reduction of nitrogen oxides in the presence of a reductant.

Abstract: Described are SCR catalyst systems comprising a first SCR catalyst composition and a second SCR catalyst composition arranged in the system, the first SCR catalyst composition promoting higher N2 formation and lower N2O formation than the second SCR catalyst composition, and the second SCR catalyst composition having a different composition than the first SCR catalyst composition, the second SCR catalyst composition promoting lower N2 formation and higher N2O formation than the first SCR catalyst composition. The SCR catalyst systems are useful in methods and systems to catalyze the reduction of nitrogen oxides in the presence of a reductant.

Abstract: Described are SCR catalyst systems comprising a first SCR catalyst composition and a second SCR catalyst composition arranged in the system, the first SCR catalyst composition promoting higher N2 formation and lower N2O formation than the second SCR catalyst composition, and the second SCR catalyst composition having a different composition than the first SCR catalyst composition, the second SCR catalyst composition promoting lower N2 formation and higher N2O formation than the first SCR catalyst composition. The SCR catalyst systems are useful in methods and systems to catalyze the reduction of nitrogen oxides in the presence of a reductant.