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.

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.

Provided herein is a catalytic article including a catalytic coating disposed on a substrate, wherein the catalytic coating comprises a bottom coating on the substrate and a top coating layer on the bottom coating layer, one such coating layer containing a platinum group metal on a refractory metal oxide support and the other such coating layer containing a ceria-containing molecular sieve. Such catalytic articles are effective toward treating exhaust gas streams of internal combustion engines and exhibit outstanding resistance to sulfur.

The invention relates to the use of a catalyst as a passive nitrogen oxide adsorber, which has a carrier substrate, a zeolite, palladium, and platinum, wherein the palladium is provided in a quantity of 0.01 to 10 wt. %, based on the sum of the weights of zeolite, platinum, and palladium and calculated as a palladium metal, and platinum in a quantity of 0.1 to 10 wt. %, based on the weight of the palladium and calculated as a platinum metal. The invention also relates to the use of said catalyst in connection with a SCR catalyst in an exhaust gas system.

The present invention relates to a catalyst comprising a macroporous noble metal-containing zeolite material and a porous SiO.sub.2-containing binder, wherein the catalyst has a proportion of micropores of more than 70%, based on the total pore volume of the catalyst. The invention is additionally directed to a process for preparing the catalyst and to the use of the catalyst as an oxidation catalyst.

The present invention relates to a catalyst comprising a macroporous noble metal-containing zeolite material and a porous SiO.sub.2-containing binder, wherein the catalyst has a proportion of micropores of more than 70%, based on the total pore volume of the catalyst. The invention is additionally directed to a process for preparing the catalyst and to the use of the catalyst as an oxidation catalyst.

The present disclosure provides msect-4 molecular sieves with OFF and ERI topologies, a preparation method therefor, and applications thereof. An eight-membered ring small pore molecular sieve used as a raw material is dispersed in an aqueous phase. Following that, caustic potash, an aluminum source, and an organic structure-directing agent (OSDA) are added. The pH value is then adjusted to be greater than 10, and a silicon source is introduced to attain the desired silicon-aluminum ratio, followed by stirring reaction, aging, crystallization, filtration, washing, ammonia exchange reaction, drying, and calcination. The msect-4 molecular sieves with OFF and ERI topologies, the preparation method therefor, and applications exhibit excellent hydrothermal stability, a plurality of adsorption sites exposed by a regular bone-like structure, and a large specific surface area. Consequently, this molecular sieves find applicability across various technical fields including selective catalytic reduction, passive adsorption, and catalytic cracking, and has broad application prospects.

The present disclosure provides msect-4 molecular sieves with OFF and ERI topologies, a preparation method therefor, and applications thereof. An eight-membered ring small pore molecular sieve used as a raw material is dispersed in an aqueous phase. Following that, caustic potash, an aluminum source, and an organic structure-directing agent (OSDA) are added. The pH value is then adjusted to be greater than 10, and a silicon source is introduced to attain the desired silicon-aluminum ratio, followed by stirring reaction, aging, crystallization, filtration, washing, ammonia exchange reaction, drying, and calcination. The msect-4 molecular sieves with OFF and ERI topologies, the preparation method therefor, and applications exhibit excellent hydrothermal stability, a plurality of adsorption sites exposed by a regular bone-like structure, and a large specific surface area. Consequently, this molecular sieves find applicability across various technical fields including selective catalytic reduction, passive adsorption, and catalytic cracking, and has broad application prospects.

A passive NO.sub.x adsorber is disclosed. The passive NO.sub.x adsorber is effective to adsorb NO.sub.x at or below a low temperature and release the adsorbed NO.sub.x at temperatures above the low temperature. The passive NO.sub.x adsorber comprises a noble metal and a molecular sieve having an OFF Framework Type. The invention also includes an exhaust system comprising the passive NO.sub.x adsorber, and a method for treating exhaust gas from an internal combustion engine utilizing the passive NO.sub.x adsorber.

A passive NO.sub.x adsorber is disclosed. The passive NO.sub.x adsorber is effective to adsorb NO.sub.x at or below a low temperature and release the adsorbed NO.sub.x at temperatures above the low temperature. The passive NO.sub.x adsorber comprises a noble metal and a molecular sieve having an OFF Framework Type. The invention also includes an exhaust system comprising the passive NO.sub.x adsorber, and a method for treating exhaust gas from an internal combustion engine utilizing the passive NO.sub.x adsorber.