Start-up method for heating a selective catalytic reduction (SCR) module in a hybrid propulsion system of a vehicle, comprising an electric motor operatively connected to an internal combustion engine producing exhaust gas, both electric motor and internal combustion engine being operable to power said vehicle, and said internal combustion engine being in fluid communication with an exhaust aftertreatment system having an exhaust passage and comprising the SCR module, said SCR module being disposed in said exhaust passage downstream of said engine and said electric motor, the method comprising the steps of: operating the engine in a start-up mode with a torque restriction on the engine, allowing the SCR module to convert NOx emission; supplying a surplus amount of a reducing agent to the exhaust gas at a position between the engine and the SCR module, the surplus amount of the reducing agent being larger than a required amount of reducing agent for converting NOx emission from the engine; heating said SCR module to a working temperature; and terminating the start-up mode, thereby terminating the torque restriction on the engine and the supply of the surplus amount of the reducing agent.

Catalysts, catalytic systems and related synthetic methods for in situ production of H.sub.2O.sub.2 and use thereof in reaction with oxidizable substrates.

Catalysts, catalytic systems and related synthetic methods for in situ production of H.sub.2O.sub.2 and use thereof in reaction with oxidizable substrates.

A catalyst article including a substrate with an inlet side and an outlet side, a first zone and a second zone, where the first zone includes an ammonia slip catalyst (ASC) comprising a platinum group metal on a support and a first SCR catalyst; where the second zone includes a catalyst selected from the group consisting of a diesel oxidation catalyst (DOC) and a diesel exotherm catalyst (DEC); and where the first zone is located upstream of the second zone. The first zone may include a bottom layer with a blend of: (1) the platinum group metal on a support and (2) the first SCR catalyst; and a top layer comprising a second SCR catalyst, the top layer located over the bottom layer.

A catalyst article including a substrate with an inlet side and an outlet side, a first zone and a second zone, where the first zone includes an ammonia slip catalyst (ASC) comprising a platinum group metal on a support and a first SCR catalyst; where the second zone includes a catalyst selected from the group consisting of a diesel oxidation catalyst (DOC) and a diesel exotherm catalyst (DEC); and where the first zone is located upstream of the second zone. The first zone may include a bottom layer with a blend of: (1) the platinum group metal on a support and (2) the first SCR catalyst; and a top layer comprising a second SCR catalyst, the top layer located over the bottom layer.

A catalyst article for treating a flow of a combustion exhaust gas comprises: a catalytically active substrate comprising one or more channels extending along an axial length thereof through which, in use, a combustion exhaust gas flows, the one or more channels having a first surface for contacting a flow of combustion exhaust gas; wherein the substrate is formed of an extruded vanadium-containing SCR catalyst material, wherein a first layer is provided on at least a portion of said first surface, wherein the first layer comprises an ammonia slip catalyst composition comprising one or more platinum group metals supported on titania, a silica-titania mixed oxide, a CeZr mixed oxide, or a mixture thereof, and a second layer is provided on at least a portion of the first layer and comprises an SCR catalyst composition.

A catalyst article for treating a flow of a combustion exhaust gas comprises: a catalytically active substrate comprising one or more channels extending along an axial length thereof through which, in use, a combustion exhaust gas flows, the one or more channels having a first surface for contacting a flow of combustion exhaust gas; wherein the substrate is formed of an extruded vanadium-containing SCR catalyst material, wherein a first layer is provided on at least a portion of said first surface, wherein the first layer comprises an ammonia slip catalyst composition comprising one or more platinum group metals supported on titania, a silica-titania mixed oxide, a CeZr mixed oxide, or a mixture thereof, and a second layer is provided on at least a portion of the first layer and comprises an SCR catalyst composition.

A method for preparing a sol comprising TiO.sub.2 and ZrO.sub.2 and/or hydrated forms of TiO.sub.2 and ZrO.sub.2. The method includes mixing a material which includes metatitanic acid in an aqueous phase with a zirconyl compound or with a mixture of several zirconyl compounds. The material is provided either as a suspension or as a filter cake from the sulfate method. The material includes a H.sub.2SO.sub.4 content of 3 to 15 wt.-% relative to a quantity of TiO.sub.2 in the material. The zirconyl compound or the mixture of several zirconyl compounds is mixed in a quantity that is sufficient to provide the sol depending on the H.sub.2SO.sub.4 content.

Methods and compositions related to a selective catalytic reduction catalyst comprising iron and vanadium, wherein the vanadium is present as (1) one or more vanadium oxides, and (2) metal vanadate of the form Fe.sub.xM.sub.yVO.sub.4 where x=0.2 to 1 and y=1x, and where M comprises one or more non-Fe metals when y>0.

The moisture-resistant catalyst for air pollution remediation is a catalyst with moisture-resistant properties, and which is used for removing nitrogen compound pollutants, such as ammonia (NH.sub.3), from air. The moisture-resistant catalyst for air pollution remediation includes at least one metal oxide catalyst, at least one inorganic oxide support for supporting the at least one metal oxide catalyst, and a porous framework for immobilizing the at least one metal oxide catalyst and the at least one inorganic oxide support, where the porous framework is moisture-resistant. As non-limiting examples, the at least one metal oxide catalyst may be supported on the at least one inorganic oxide support by precipitation, impregnation, dry milling, ion-exchange or combinations thereof. The at least one metal oxide catalyst supported on the at least one inorganic oxide support may be physically embedded in the porous framework.