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 disclosure relates to oxidation catalyst compositions for use in a close-coupled diesel oxidation catalyst (ccDOC) application, in which the ccDOC can function as a heat generator under high space velocity conditions. The oxidation catalyst compositions include a high surface area support material doped with at least one metal oxide, and a platinum group metal (PGM) supported on the doped high surface area support material.

Abstract: This disclosure relates to devices and methods for coating various portions of catalyst support bodies, such as radially-zoned catalyst support bodies, such as those used in catalytic converters for treating exhaust gas streams of internal combustion engines.

Abstract: Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N2O formation. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles have zoned coatings containing copper-containing molecular sieves disposed thereon, where for example a concentration of catalytic copper in an upstream zone is lower than the concentration of catalytic copper in a downstream zone.

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: Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N2O formation. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles have zoned coatings disposed thereon, for example, a zoned coating comprising an upstream zone comprising a coating layer comprising a steam-activated iron-containing molecular sieve and a downstream zone comprising a coating layer comprising a high copper-containing molecular sieve.

Abstract: A system for treatment of an exhaust gas stream from an engine is provided, containing an upstream selective catalytic reduction (SCR) catalyst, which receives the exhaust gas stream without any intervening catalyst, a diesel oxidation catalyst (DOC) positioned downstream thereof; a catalyzed soot filter (CSF) downstream of the diesel oxidation catalyst; a second SCR catalyst positioned downstream of the catalyzed soot filter; and an ammonia oxidation (AMOx) catalyst. The application also describes use of such systems to reduce nitrogen oxides (NOx) and hydrocarbons (HC) in an exhaust gas stream.

Abstract: Described are exhaust gas treatment systems for treatment of an engine exhaust gas stream containing NOx. The exhaust gas treatment system comprises an engine, a catalyst system including a selective catalytic reduction article comprising two zones, an upstream zone comprising iron-promoted first molecular sieves and a downstream zone comprising copper-promoted second molecular sieves. The catalyst system is effective to reduce high NOx levels in the exhaust gas stream. Also described are methods for treatment of engine exhaust gas streams, comprising treating engine exhaust gas streams containing high NOx levels with catalyst systems including selective catalytic reduction articles having two zones.

Abstract: A system for treatment of an exhaust gas stream from an engine is provided, containing an upstream selective catalytic reduction (SCR) catalyst, which receives the exhaust gas stream without any intervening catalyst, a diesel oxidation catalyst (DOC) positioned downstream thereof; a catalyzed soot filter (CSF) downstream of the diesel oxidation catalyst; a second SCR catalyst positioned downstream of the catalyzed soot filter; and an ammonia oxidation (AMOx) catalyst. The application also describes use of such systems to reduce nitrogen oxides (NOx) and hydrocarbons (HC) in an exhaust gas stream.

Abstract: Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N2O formation. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles have zoned coatings containing copper-containing molecular sieves disposed thereon, where for example a concentration of catalytic copper in an upstream zone is lower than the concentration of catalytic copper in a downstream zone.

Abstract: Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N2O formation. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles have zoned coatings disposed thereon, for example, a zoned coating comprising an upstream zone comprising a coating layer comprising a steam-activated iron-containing molecular sieve and a downstream zone comprising a coating layer comprising a high copper-containing molecular sieve.

Abstract: Described are exhaust gas treatment systems for treatment of an engine exhaust gas stream containing NOx. The exhaust gas treatment system comprises an engine, a catalyst system including a selective catalytic reduction article comprising two zones, an upstream zone comprising iron-promoted first molecular sieves and a downstream zone comprising copper-promoted second molecular sieves. The catalyst system is effective to reduce high NOx levels in the exhaust gas stream. Also described are methods for treatment of engine exhaust gas streams, comprising treating engine exhaust gas streams containing high NOx levels with catalyst systems including selective catalytic reduction articles having two zones.