Abstract: The present invention relates to an exhaust gas treatment system for reducing ammonia emission from a gasoline engine comprising a three-way conversion catalyst (TWC) or a four-way conversion catalyst (FWC), further comprising an ammonia oxidation catalyst (AMOx) or a selective catalytic reduction catalyst (SCR), and a method of treating exhaust gas from a gasoline engine with an exhaust gas treatment system capable of removing ammonia.

Abstract: Catalyzed particulate filters comprise three-way conversion (TWC) catalytic material, which comprises rhodium as the only platinum group metal, that permeates walls of a particulate filter. Such catalyzed particulate filters may be located downstream of close-coupled three-way conversion (TWC) composites in an emission treatment system downstream of a gasoline direct injection engine for treatment of an exhaust stream comprising hydrocarbons, carbon monoxide, nitrogen oxides, and particulates.

Abstract: The present invention relates to a zoned catalytic article, particularly useful for TWC, which comprises: a) a catalyst composition coat comprising a first zone of the catalyst composition coat, comprising a platinum group metal component consisting of a platinum component supported on a support; and a second zone of the catalyst composition coat, comprising a rhodium component and at least one of a platinum component and a palladium component supported individually or together on a support, and b) a substrate; wherein the first zone and the second zone of the catalyst composition coat are carried on a single piece of substrate or carried on respective pieces of substrate useful for treatment of exhaust gases and an exhaust treatment system comprising the zoned catalytic article. The present invention also relates to an exhaust treatment system comprising the zoned catalytic article.

Abstract: Catalyzed particulate filters comprise three-way conversion (TWC) catalytic material, which comprises rhodium as the only platinum group metal, that permeates walls of a particulate filter. Such catalyzed particulate filters may be located downstream of close-coupled three-way conversion (TWC) composites in an emission treatment system downstream of a gasoline direct injection engine for treatment of an exhaust stream comprising hydrocarbons, carbon monoxide, nitrogen oxides, and particulates.

Abstract: Catalyzed particulate filters comprise three-way conversion (TWC) catalytic material, which comprises rhodium as the only platinum group metal, that permeates walls of a particulate filter. Such catalyzed particulate filters may be located downstream of close-coupled three-way conversion (TWC) composites in an emission treatment system downstream of a gasoline direct injection engine for treatment of an exhaust stream comprising hydrocarbons, carbon monoxide, nitrogen oxides, and particulates.

Abstract: Catalyzed particulate filters comprise three-way conversion (TWC) catalytic material, which comprises rhodium as the only platinum group metal, that permeates walls of a particulate filter. Such catalyzed particulate filters may be located downstream of close-coupled three-way conversion (TWC) composites in an emission treatment system downstream of a gasoline direct injection engine for treatment of an exhaust stream comprising hydrocarbons, carbon monoxide, nitrogen oxides, and particulates.

Abstract: A layered catalyst composite for the treatment of exhaust gas emissions, effective to provide lean NOx trap functionality and three-way conversion functionality is described. Layered catalyst composites can comprise catalytic material on a substrate, the catalytic material comprising at least two layers. The first layer comprising rare earth oxide-high surface area refractory metal oxide particles, an alkaline earth metal supported on the rare earth oxide-high surface area refractory metal oxide particles, and at least one first platinum group metal component supported on the rare earth oxide-high surface area refractory metal oxide particles. The second layer comprising a second platinum group metal component supported on a first oxygen storage component (OSC) and/or a first refractory metal oxide support and, optionally, a third platinum group metal supported on a second refractory metal oxide support or a second oxygen storage component.

Abstract: A layered catalyst composite for the treatment of exhaust gas emissions, effective to provide lean NOx trap functionality and three-way conversion functionality is described. Layered catalyst composites can comprise catalytic material on a substrate, the catalytic material comprising at least two layers. The first layer comprising rare earth oxide-high surface area refractory metal oxide particles, an alkaline earth metal supported on the rare earth oxide-high surface area refractory metal oxide particles, and at least one first platinum group metal component supported on the rare earth oxide-high surface area refractory metal oxide particles. The second layer comprising a second platinum group metal component supported on a first oxygen storage component (OSC) and/or a first refractory metal oxide support and, optionally, a third platinum group metal supported on a second refractory metal oxide support or a second oxygen storage component.

Abstract: A layered catalyst composite for the treatment of exhaust gas emissions, effective to provide lean NOx trap functionality and three-way conversion functionality is described. Layered catalyst composites can comprise catalytic material on a substrate, the catalytic material comprising at least two layers. The first layer comprising rare earth oxide-high surface area refractory metal oxide particles, an alkaline earth metal supported on the rare earth oxide-high surface area refractory metal oxide particles, and at least one first platinum group metal component supported on the rare earth oxide-high surface area refractory metal oxide particles. The second layer comprising a second platinum group metal component supported on a first oxygen storage component (OSC) and/or a first refractory metal oxide support and, optionally, a third platinum group metal supported on a second refractory metal oxide support or a second oxygen storage component.

Abstract: A layered catalyst composite for the treatment of exhaust gas emissions, effective to provide lean NOx trap functionality and three-way conversion functionality is described. Layered catalyst composites can comprise catalytic material on a substrate, the catalytic material comprising at least two layers. The first layer comprising rare earth oxide-high surface area refractory metal oxide particles, an alkaline earth metal supported on the rare earth oxide-high surface area refractory metal oxide particles, and at least one first platinum group metal component supported on the rare earth oxide-high surface area refractory metal oxide particles. The second layer comprising a second platinum group metal component supported on a first oxygen storage component (OSC) and/or a first refractory metal oxide support and, optionally, a third platinum group metal supported on a second refractory metal oxide support or a second oxygen storage component.

Abstract: Diesel exhaust treatment articles, systems and methods are disclosed. According to one or more embodiments, an oxygen storage component is utilized and degradation of the oxygen storage component is correlated with degradation of the hydrocarbon conversion efficiency of a catalyst in a diesel engine system.

Abstract: Diesel exhaust treatment articles, systems and methods are disclosed. According to one or more embodiments, an oxygen storage component is utilized and degradation of the oxygen storage component is correlated with degradation of the hydrocarbon conversion efficiency of a catalyst in a diesel engine system.