B01J29/56

Selective catalytic reduction articles and systems

Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N.sub.2O 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.

Selective catalytic reduction articles and systems

Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N.sub.2O 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.

Catalyst and manufacturing method thereof

The present disclosures relate to a catalyst for removing a nitrogen oxide and a manufacturing method thereof, and the catalyst for removing the nitrogen oxide includes: a first catalyst that includes a zeolite support containing copper and having a first framework; and a second catalyst that is physically mixed with the first catalyst and includes a zeolite support containing copper and having a second framework different from the first framework.

Catalyst and manufacturing method thereof

The present disclosures relate to a catalyst for removing a nitrogen oxide and a manufacturing method thereof, and the catalyst for removing the nitrogen oxide includes: a first catalyst that includes a zeolite support containing copper and having a first framework; and a second catalyst that is physically mixed with the first catalyst and includes a zeolite support containing copper and having a second framework different from the first framework.

Catalyst for oxidising ammonia
RE049743 · 2023-12-05 ·

A catalyst for oxidising ammonia comprises a selective catalytic reduction (SCR) catalyst and a composite heterogeneous extruded honeycomb having longitudinally extending parallel channels, which channels being defined in part by channel walls having a total longitudinal length, wherein the channel walls comprise a pore structure including a periodic arrangement of porous cells embedded in an inorganic matrix component, at least some of which porous cells are defined at least in part by an active interface layer of a catalytically active material comprising a precious metal supported on particles of a support material.

Catalyst for oxidising ammonia
RE049743 · 2023-12-05 ·

A catalyst for oxidising ammonia comprises a selective catalytic reduction (SCR) catalyst and a composite heterogeneous extruded honeycomb having longitudinally extending parallel channels, which channels being defined in part by channel walls having a total longitudinal length, wherein the channel walls comprise a pore structure including a periodic arrangement of porous cells embedded in an inorganic matrix component, at least some of which porous cells are defined at least in part by an active interface layer of a catalytically active material comprising a precious metal supported on particles of a support material.

Palladium/zeolite-based passive nitrogen oxide adsorber catalyst for purifying exhaust gas

The invention relates to a catalyst which comprises a carrier substrate, palladium, and a zeolite, the largest channels of which are formed by 10 tetradrically coordinated atoms; to the use of said catalyst as a passive nitrogen oxide adsorber, an exhaust gas system which contains said catalyst and an SCR catalyst, and to a method for purifying the exhaust gas of motor vehicles using said exhaust gas system.

Crystalline zeolites with ERI/CHA intergrowth framework type

The present invention relates to crystalline zeolites with an ERI/CHA intergrowth framework type and to a process for making said zeolites. The ERI content of the zeolites ranges from 10 to 85 wt.-%, based on the total weight of ERI and CHA. The zeolites may further comprise 0.1 to 10 wt.-% copper, calculated as CuO, and one or more alkali and alkaline earth metal cations in an amount of 0.1 to 5 wt.-%, calculated as pure metals. The process for making the zeolites with an ERI/CAH intergrowth framework type comprises a) the preparation of a first aqueous reaction mixture comprising a zeolite of the faujasite framework type, Cu-TEPA and a base M(OH), b) the preparation of a second aqueous reaction mixture comprising a silica source, an alumina source, an alkali or alkaline earth metal chloride, bromide or hydroxide, a quaternary alkylammonium salt and hexamethonium bromide, c) combining the two reaction mixtures, and d) heating the combination of the two reaction mixtures to obtain a zeolite with an ERI/CHA intergrowth framework type. The ERI/CHA intergrowth zeolite may subsequently be calcined. The zeolites according to the present invention are suitable SCR catalysts.

Crystalline zeolites with ERI/CHA intergrowth framework type

The present invention relates to crystalline zeolites with an ERI/CHA intergrowth framework type and to a process for making said zeolites. The ERI content of the zeolites ranges from 10 to 85 wt.-%, based on the total weight of ERI and CHA. The zeolites may further comprise 0.1 to 10 wt.-% copper, calculated as CuO, and one or more alkali and alkaline earth metal cations in an amount of 0.1 to 5 wt.-%, calculated as pure metals. The process for making the zeolites with an ERI/CAH intergrowth framework type comprises a) the preparation of a first aqueous reaction mixture comprising a zeolite of the faujasite framework type, Cu-TEPA and a base M(OH), b) the preparation of a second aqueous reaction mixture comprising a silica source, an alumina source, an alkali or alkaline earth metal chloride, bromide or hydroxide, a quaternary alkylammonium salt and hexamethonium bromide, c) combining the two reaction mixtures, and d) heating the combination of the two reaction mixtures to obtain a zeolite with an ERI/CHA intergrowth framework type. The ERI/CHA intergrowth zeolite may subsequently be calcined. The zeolites according to the present invention are suitable SCR catalysts.

Ion-exchanged molecular sieve catalysts exhibiting reduced N2O emissions

The present disclosure generally provides catalysts, catalyst articles and catalyst systems including such catalyst articles. In particular, the catalyst composition includes a metal ion-exchanged molecular sieve ion-exchanged with at least one additional metal, which reduces the number of metal centers often present in metal promoted zeolite catalysts. Methods of making and using the catalyst composition are also provided, as well as emission treatment systems including a catalyst article coated with the catalyst composition. The catalyst article present in such emission treatment systems is useful to catalyze the reduction of nitrogen oxides in gas exhaust in the presence of a reductant while minimizing the amount of dinitrogen oxide emission.