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.

A particulate filter having a porous ceramic honeycomb structure with a first end, a second end, and a plurality of walls having wall surfaces defining a plurality of inner channels. Filtration material deposits are disposed on one or more of the wall surfaces of the honeycomb body. The highly porous deposits provide durable high clean filtration efficiency with small impact on pressure drop through the filter.

An exhaust gas purification catalyst apparatus has a honeycomb base material and a catalyst noble metal supported by the honeycomb base material, wherein: the honeycomb base material contains ceria-zirconia composite oxide particles as one of the constituent materials, is of a wall flow type, and includes inlet-side cells and outlet-side cells demarcated by porous partition walls; the catalyst noble metal is supported in inlet-side support regions and outlet-side support regions; each of the inlet-side support regions is formed with a specific length from the exhaust gas flow upstream end; the catalyst noble metal 70% support depth is not greater than 50% of the thickness of the porous partition walls; each of the outlet-side support regions is formed with a specific length from the exhaust gas flow downstream end; and the catalyst noble metal 70% support depth is greater than 50% of the thickness of the porous partition walls.

The present invention relates to a catalyst washcoat composition comprising a slurry comprising at least one platinum group metal and/or at least one non-platinum group metal supported on at least one support; and at least one pore forming agent having a particle size ranging from 100 nm to 5.0 μm, wherein the pore forming agent is selected from carbon nano-tubes, carbon nano-fibres, activated carbon, resins, cellulose powder, and polymer spheres. The present invention also provides a catalyst article for capturing particulate matter of size ranging from 1.0 nm to 100 μm, said article comprising the catalyst washcoat deposited on a substrate and calcined to form pores of which 50%-100% have a pore size ranging from 100 nm to 5.0 μm.

The present disclosure provides Low Temperature NO.sub.x-Absorber (LT-NA) catalyst compositions, catalyst articles, and an emission treatment system for treating an exhaust gas, each including the LT-NA catalyst compositions. Further provided are methods for reducing a NO.sub.x level in an exhaust gas stream using the LT-NA catalyst articles. In particular, the LT-NA catalyst compositions include a first zeolite, a first palladium component, and a plurality of platinum nanoparticles. The LT-NA catalyst compositions exhibit enhanced regeneration efficiency with respect to NO.sub.x adsorption capacity, even after hydrothermal aging.

Emissions treatment systems of combustion engines are provided, which comprise a platinum-containing catalyst that is degreened during production, which is before exposure to operating conditions of a vehicle having a diesel engine. The platinum-containing catalyst, in the form of a platinum component on a high surface area refractory metal oxide support, exhibits a vibration frequency of about 2085 to about 2105 cm.sup.−1 as measured by CO-DRIFTS. Such catalytic material is essentially-free of platinum oxide species found at greater than about 2110 cm.sup.−1 as measured by CO-DRIFTS. Such catalysts can provide excellent and consistent conversion of nitrogen oxide (NO) to nitrogen dioxide (NO.sub.2).

An exhaust gas purification catalyst including particles of a catalyst metal supported on secondary particles of an inorganic oxide, wherein when scanning transmission electron microscope-energy dispersive X-ray line analysis is performed from a surface of the secondary particles toward a center thereof, a support density of the catalyst metal on a surface side of the secondary particles is greater than the support density of the catalyst metal in a center part of the secondary particles.

The present invention relates to a catalyst comprising a carrier substrate of length L and at least two washcoat layers A and B wherein washcoat layer A comprises alumina; ceria; an alkaline earth compound and/or an alkali compound; platinum, palladium or platinum and palladium; washcoat layer B comprises a zeolite and palladium, wherein the palladium is present as palladium cation in the zeolite structure or is wholly or partially present as palladium metal and/or as palladium oxide in the zeolite structure and/or on the surface of the zeolite structure; and
wherein washcoat layer A is arranged below washcoat layer B.

An ozone purification catalyst, and a preparation method therefor and an application thereof are provided. The catalyst coating uses macroporous, high specific surface and CeO.sub.2 and/or La.sub.2O.sub.3 modified Al.sub.2O.sub.3 as the carrier material, and Mn and/or Pd as the active component. The preparation method is to prepare the Al.sub.2O.sub.3-based material by a sol-gel method, and then to load the active components on the carrier material, and to dry, calcinate and solidify to obtain the ozone purification catalyst. The catalysts as prepared shows a fast and efficient purification of ozone. The complete conversion temperature covers a wide range of temperature. The catalyst has excellent texture performance, high specific surface area and large pore volume, which is beneficial to ozone purification when the car is running at high speed. The particle sizes and colors of the catalyst can be modified according to various requirements. According to the actual application, it can be coated on the radiator fins of automobile water tanks, and any place where coating is allowed in public areas such as urban bus stations, stop signs, kiosks, roadside guardrails, or exterior walls of buildings that is in contact with outdoor air.

A substrate (11) of an exhaust gas purification catalyst (10) includes inflow-side cells (21), outflow-side cells (22), and porous partition walls (23), each separating the inflow-side cell and the outflow-side cell. Catalyst portions (14, 15) are provided on the surfaces of the partition walls that each face the inflow-side cell and/or the surfaces of the partition walls that each face the outflow-side cell. In a cross section vertical to an exhaust gas flow direction, the percentage of the total area of voids, each void satisfying the expression L/{2(πS).sup.1/2}≤1.1 (wherein L is the perimeter of the void in the cross section, and S is the area of the void in the cross section), is greater than 10% to 30% or less based on the apparent area of the catalyst portion present on the partition wall. The content of zirconium element in terms of oxide (amount of ZrO2) in the catalyst portions is from 35 mass % to 85 mass %.