The moisture-resistant catalyst for air pollution remediation is a catalyst with moisture-resistant properties, and which is used for removing nitrogen compound pollutants, such as ammonia (NH.sub.3), from air. The moisture-resistant catalyst for air pollution remediation includes at least one metal oxide catalyst, at least one inorganic oxide support for supporting the at least one metal oxide catalyst, and a porous framework for immobilizing the at least one metal oxide catalyst and the at least one inorganic oxide support, where the porous framework is moisture-resistant. As non-limiting examples, the at least one metal oxide catalyst may be supported on the at least one inorganic oxide support by precipitation, impregnation, dry milling, ion-exchange or combinations thereof. The at least one metal oxide catalyst supported on the at least one inorganic oxide support may be physically embedded in the porous framework.

A cerium-zirconium-aluminum-based composite material, a cGPF catalyst and a preparation method thereof are provided. The cerium-zirconium-aluminum-based composite material adopts a stepwise precipitation method, firstly preparing an aluminum-based pre-treated material, then coprecipitating the aluminum-based pre-treated material with zirconium and cerium sol, and finally roasting at high temperature to obtain the cerium-zirconium-aluminum-based composite material. The cerium-zirconium-aluminum-based composite material has better compactness and higher density, and when it is used in cGPF catalyst, it occupies a smaller volume of pores on the catalyst carrier, such that cGPF catalyst has lower back pressure and better ash accumulation resistance, which is beneficial to large-scale application of cGPF catalyst.

The present invention relates to a mixed oxide of aluminium, of zirconium, of cerium, of lanthanum and optionally of at least one rare-earth metal other than cerium and lanthanum that makes it possible to prepare a catalyst that retains, after severe ageing, a good thermal stability and a good catalytic activity. The invention also relates to the process for preparing this mixed oxide and also to a process for treating exhaust gases from internal combustion engines using a catalyst prepared from this mixed oxide.

A honeycomb-structured catalyst for decomposing an organic substance, which includes a catalyst particle. The catalyst particle contains a perovskite-type composite oxide represented by A.sub.xB.sub.yM.sub.zO.sub.w, where the A contains at least of Ba and Sr, the B contains Zr, the M is at least one of Mn, Co, Ni, and Fe, y+z=1, 1.001≤x≤1.05, 0.05≤z≤0.2, and w is a positive value that satisfies electrical neutrality. The toluene decomposition rate is greater than 90% when toluene is decomposed using the honeycomb-structured catalyst subjected to a heat treatment at 1200° C. for 48 hours and a gas that contains 50 ppm toluene, 80% nitrogen, and 20% oxygen as a volume concentration as a target at a space velocity of 30,000/h and a catalyst temperature of 400° C.

A cerium-zirconium oxide-based ionic conductor (CZOIC) material including zirconium oxide in an amount ranging from 5 wt. % up to 95 wt. %, cerium oxide in an amount ranging from 95 wt. % to 5 wt. %, and at least one oxide or a rare earth metal in an amount ranging from 30 wt. % or less, based on the overall mass of the CZOIC material. The CZOIC material exhibits a structure comprising one or more expanded unit cells and a plurality of crystallites having ordered nano-domains. The structure of the CZOIC material exhibits a crystal lattice defined by a d-value measured at multiple (hkl) locations using a SAED technique that exhibit distortions, such that the d-values for the same (hkl) location varies from about 2% to about 5% from the d-value measured for a reference cerium-zirconium material at the same (hkl) location.

Methods for exhaust gas purification, including the steps of: attaching an exhaust gas purification catalyst to an exhaust system of an internal combustion engine, and supplying an exhaust gas to the exhaust gas purification catalyst, where the exhaust gas purification catalyst includes an upper layer containing first carrier particles which are particles of an inorganic oxide and rhodium, and a lower layer containing second carrier particles which are particles of an inorganic oxide, the upper layer includes a rhodium-rich portion near the surface of the upper layer on the upstream side of the exhaust gas flow, and the existence range of the rhodium-rich portion is in a range of greater than 50% to 80% of the length of the upper layer from a downstream side end of an exhaust gas flow and of less than 20 μm in the depth direction from an outermost surface of the upper layer.

A composition for exhaust gas purification containing Y—Mn—O and Al.sub.2O.sub.3 and having a specific surface area (SSA) retention satisfying inequality (1) SSA retention (%) >−61.54×(Y—Mn—O ratio)+75.55 and inequality (2) SSA retention (%) >45 (2), where SSA retention is represented by (SSA after aging)/(initial SSA)×100 (%). The SSA after aging and the initial SSA are as defined in the description. The Y—Mn—O ratio is a mass ratio of Y—Mn—O to the sum of Y—Mn—O and Al.sub.2O.sub.3 in the composition for exhaust gas purification, being represented by Y—Mn—O/(Y—Mn—O+Al.sub.2O.sub.3).

Methods for exhaust gas purification, including the steps of: attaching an exhaust gas purification catalyst to an exhaust system of an internal combustion engine, and supplying an exhaust gas to the exhaust gas purification catalyst, where the exhaust gas purification catalyst includes an upper layer containing first carrier particles which are particles of an inorganic oxide and rhodium, and a lower layer containing second carrier particles which are particles of an inorganic oxide, the upper layer includes a rhodium-rich portion near the surface of the upper layer on the upstream side of the exhaust gas flow, and the existence range of the rhodium-rich portion is in a range of greater than 50% to 80% of the length of the upper layer from a downstream side end of an exhaust gas flow and of less than 20 μm in the depth direction from an outermost surface of the upper layer.

The present invention relates to a particulate filter which comprises a wall-flow filter of length L and two different catalytically active coatings Y and Z, wherein the wall flow filter comprises channels E and A that extend in parallel between a first and a second end of the wall-flow filter and are separated by porous walls which form the surfaces O.sub.E and O.sub.A, respectively, and wherein the channels E are closed at the second end and the channels A are closed at the first end. The invention is characterized in that the coating Y is located in the channels E on the surfaces O.sub.E and the coating Z is located in the porous walls.

In an aspect of the present disclosure, a catalyst includes an oxide containing 5 or more types of rare earth elements and 1 or more types of platinum group elements. The catalyst has a configuration entropy of a cation site determined based on (i) the number of types of the rare earth elements and the platinum group element that can be arranged in the cation site in a crystalline structure of the oxide, and (ii) each proportion of the rare earth elements and the platinum group element of more than 1.7R, where R is a gas constant.