The present invention provides an exhaust gas purification catalyst including a base material 11 and a catalyst layer 20 provided on the base material 11. The catalyst layer 20 includes: a catalyst metal; and a carrying material 21 carrying the catalyst metal. The carrying material 21 includes: an OSC material 22 having an oxygen storage capacity; and a carrier 23 other than the OSC material. The OSC material 22 has a mean particle diameter Dx of 1.5 μm or more which is larger than the mean particle diameter Dy of the carrier 23 other than the OSC material 22.

An exhaust gas cleaning catalyst is provided with a fire-resistant three-dimensional structural body, a first catalyst layer provide on a first surface side of the fire-resistant three-dimensional structural body, and a second catalyst layer provided on a side of the first catalyst layer opposite to the fire-resistant three-dimensional structural body. The first catalyst layer contains: a complex oxide including cerium and zirconium; and elemental rhodium. The second catalyst layer contains: a complex oxide including cerium and zirconium; and elemental palladium. The amount of cerium included in the second catalyst layer, in terms of cerium dioxide, is 10-25 g per liter of the fire-resistant three-dimensional structural body.

A NOx adsorber catalyst for treating an exhaust gas from a diesel engine. The NOx adsorber catalyst comprises a first region comprising a NOx adsorber material comprising a first molecular sieve catalyst. The first molecular sieve catalyst comprises a first noble metal and a first molecular sieve, and the first molecular sieve contains the noble metal. The first molecular sieve has an STI Framework Type.

The present disclosure is directed to an emission treatment system for oxidation of hydrocarbons and carbon monoxide and for NO.sub.x abatement in an exhaust stream of a lean burn engine, the emission treatment system including a low-temperature NO.sub.x adsorber (LT-NA) that includes a molecular sieve impregnated with at least one PGM component positioned in fluid communication with the exhaust stream; and an oxidation catalyst that includes a refractory metal oxide support containing manganese impregnated with platinum positioned in fluid communication with the exhaust stream, each of the LT-NA and the oxidation catalyst being disposed on a substrate. The invention provides a catalyst article combining an oxidation catalyst with a LT-NA and a related method of treatment of an exhaust gas.

The present disclosure is directed to Low Temperature NOx-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 catalyst article. In particular, the LT-NA compositions include a zeolite containing a first metal component including palladium and a second metal component which is an alkaline earth metal component, an oxide of an alkaline earth metal component, a rare earth metal component, an oxide of a rare earth metal component, or a combination thereof. The LT-NA compositions exhibit increased low temperature NO.sub.x adsorption capacity and enhanced hydrothermal stability.

There is provided a structure including: a substrate including a first and a second ends, and a porous partition wall defining a first and a second cells extending between the first and the second ends; a first catalyst; and a second catalyst. In a first area, the first catalyst is disposed on a first surface of the partition wall, and the partition wall with the first catalyst disposed on the partition wall is impermeable to gas. In a second area, the first catalyst is not provided, the second catalyst is disposed in a region including at least a part inside the partition wall, the part facing the first cell, and the partition wall with the second catalyst disposed in the partition wall is permeable to gas. In a third area, any of the first catalyst or the second catalyst is not provided, and the partition wall is permeable to gas.

An improved SCRoF (selective catalytic reduction on filter) device for treating exhaust from an internal combustion engine. The filter has numerous entry and exit channels. Exhaust enters the entry channels and flows through side walls into the exit channels. Relative to the exhaust flow path, these side walls are coated on the downstream side with a ceria-based catalyst and on the upstream side with a Cu-zeolite catalyst. This allows the filter to optimally achieve both particulate matter oxidation and NOx reduction, respectively.

The present invention relates to the use of a material B containing palladium and platinum in a weight ratio of 2:3 to 10:1 for increasing the low-temperature storage of nitrogen oxides by means of a material A containing palladium and zeolite, wherein material A and material B are present on a carrier substrate of the length L, and wherein material A and material B are different from one another.

The invention relates to a catalytic converter for removing carbon monoxide, hydrocarbons and nitrogen oxides from the exhaust gas of internal combustion engines operated with stoichiometric air-fuel mixture, which catalytic converter comprises a substrate of the length L and a catalytic coating, characterized in that the coating is located on the walls of the substrate and extends, proceeding from one end of the substrate, over a length corresponding to at least 50% of L and comprises active aluminum oxide, two cerium/zirconium/rare-earth-metal mixed oxides different from each other, and at least one platinum group metal.

An exhaust gas purification catalyst is provided which can be more enhanced in NOx purification performance. An exhaust gas purification catalyst including a substrate, a NOx storage layer located over the substrate, an oxidation catalyst layer located over a part of the NOx storage layer, the part being located upstream in an exhaust gas flow direction, and a reduction catalyst layer located over a part of the NOx storage layer, the part being located downstream in an exhaust gas flow direction, wherein the NOx storage layer includes an oxidation catalyst including Pd or Pd and Pt, and a NOx storage material including at least one element selected from the group consisting of an alkali metal, an alkali earth metal and a rare-earth element, the oxidation catalyst layer includes an oxidation catalyst including Pt or Pt and Pd, the reduction catalyst layer includes a reduction catalyst including Rh, and a total content rate (mol %) of Pt and Pd based on a total content rate (100 mol %) of metal element(s) in the oxidation catalyst layer is higher than a total content rate (mol %) of Pt and Pd based on a total content rate (100 mol %) of metal elements in the NOx storage layer.