A nitrous oxide (N.sub.2O) removal catalyst composite is provided, comprising a N.sub.2O removal catalytic material on a substrate, the catalytic material comprising a rhodium (Rh) component supported on a ceria-based support, wherein the catalyst composite has a H.sub.2-consumption peak of about 100° C. or less as measured by hydrogen temperature-programmed reduction (H.sub.2-TPR). Methods of making and using the same are also provided.

Provided is an exhaust gas purification catalyst improved in warm-up performance while suppressing HC poisoning of a noble metal in an atmosphere in which an air-fuel ratio (A/F) is rich and the HC poisoning easily occurs. The present disclosure relates to an exhaust gas purification catalyst that includes a substrate and a catalyst coating layer coated on the substrate. The catalyst coating layer includes a lower coating layer coated on the substrate and an upper coating layer coated on the lower coating layer. The lower coating layer contains a noble metal. The upper coating layer contains Pd and/or Pt. The Pd and/or Pt contained in the upper coating layer is supported on A1.sub.2O.sub.3 by a certain amount or more. A thickness of the upper coating layer is adjusted.

The present disclosure relates to a method of producing a catalyst for exhaust gas purification, including: (i) a process in which a Pd precursor and a Pt precursor are dissolved in a solvent to prepare a solution containing Pd and Pt, the content of Pt with respect to a total weight of Pd and Pt being 85 weight % or less; and (ii) a process in which the solution containing Pd and Pt prepared in the process (i) is supported on a catalyst coating layer.

Provided is an exhaust gas purification device that allows improving an exhaust gas purification performance. An exhaust gas purification device of the present disclosure includes a substrate and a catalyst layer disposed on the substrate. The catalyst layer contains a porous carrier, a catalytic metal that is supported by the porous carrier and belongs to platinum group, an alkaline earth metal supported by the porous carrier, and an alkaline earth metal not supported by the porous carrier. At least a part of the alkaline earth metal supported by the porous carrier is supported inside the porous carrier.

The present invention provides a catalytic article comprising a) a first layer comprising a nickel component and a copper component supported on a ceria component, wherein the amount of the nickel component is 0.1 to 30 wt. %, calculated as nickel oxide, based on the total weight of the first layer, and wherein the amount of the copper component is 0.01 to 5.0 wt. % calculated as copper oxide, based on the total weight of the first layer; b) a second layer comprising a platinum group metal component supported on at least one of an oxygen storage component, an alumina component and a zirconia component, wherein the platinum group metal component comprises platinum, rhodium, palladium, or any combination thereof, and wherein the amount of the platinum group metal component is 0.01 to 5.0 wt. % based on the total weight of the second layer; and c) a substrate, wherein the first layer and the second layer are separated by a barrier layer or a gap.

Described are a catalyst capable of effectively oxidizing an exhaust gas, a method for preparing the catalyst, and a method for oxidizing an exhaust gas using the catalyst. The exhaust gas oxidation catalyst includes at least two layers, a lower catalyst layer and an upper catalyst layer, laminated on a three-dimensional structure, wherein the lower catalyst layer and the upper catalyst layer independently contain precious metal and alumina and/or zeolite, and at least a part of the upper catalyst layer contains pores derived from a pore connecting agent with a combustion decomposition temperature of 300° C. or more to less than 450° C.

Catalyzed particulate filters comprise three-way conversion (TWC) catalytic material that permeates walls of a particulate filter such that the catalyzed particulate filter has a coated porosity that is less than an uncoated porosity of the particulate filter. The coated porosity is linearly proportional to a washcoat loading of the TWC catalytic material. A coated backpressure is non-detrimental to performance of the engine. Such catalyzed particulate filters may be used 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.

A lean NO.sub.x trap catalyst and its use in an emission treatment system for internal combustion engines is disclosed. The lean NO.sub.x trap catalyst comprises a first layer for storing nitrogen oxides (NOx) under lean exhaust gas conditions and releasing and/or reducing stored NOx during rich exhaust gas conditions, and a second layer, said second layer comprising a first zone for oxidizing carbon monoxide (CO) and/or hydrocarbons (HC), and a second zone for oxidizing nitric oxide (NO), and a substrate having an inlet end and an outlet end.

Disclosed are a mixed oxide composition based on zirconium and cerium exhibiting a high reducibility, the process for preparing it and its use in the field of catalysis.

A nitrous oxide (N.sub.2O) removal catalyst composite is provided, comprising a N.sub.2O removal catalytic material on a substrate, the catalytic material comprising a rhodium (Rh) component supported on a ceria-based support, wherein the catalyst composite has a H.sub.2-consumption peak of about 100° C. or less as measured by hydrogen temperature-programmed reduction (H.sub.2-TPR). Methods of making and using the same are also provided.