The present invention relates generally to the field of exhaust treatment systems for purifying exhaust gas discharged from a lean burn engine. The exhaust treatment system comprises a Diesel Oxidation Catalyst (DOC), a Catalyzed Soot Filter (CSF), a reductant injector, an AEI zeolite based Selective Catalyzed Reduction (SCR) catalyst and an Ammonia Oxidation Catalyst (AMOX) downstream to the AEI zeolite based SCR catalyst.

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 process for coating substrates of motor vehicle exhaust gas catalysts is described, and includes steps of applying a suspension (e.g., washcoat) to a substrate, allowing a shear force to act on the applied washcoat, as in pressure transmitted by gas (e.g., air), and then sucking and/or pressing the washcoat into the substrate. The process in inclusive of providing the suspension (washcoat) containing the catalytic material from above in a metered charge process. An apparatus for carrying out the noted process steps is also featured.

The present invention provides an exhaust gas purification catalyst including an alkaline earth metal supported in a highly dispersed state on a porous carrier. A catalyst layer of the exhaust gas purification catalyst provided by the invention has an alkaline earth metal-supporting region including a porous carrier, a catalyst metal belonging to the platinum group, and a sulfate of at least one type of alkali earth metal supported on the porous carrier. In a cross-section of this region, a Pearson correlation coefficient R.sub.Ae/M is at least 0.5 as calculated using α and β for each pixel obtained by carrying out area analysis by FE-EPMA under conditions of pixel size of 0.34 μm×0.34 μm, and measured pixel number 256×256, and by measuring the characteristic X-ray intensity (α:cps) of the alkaline earth metal element (Ae) and the characteristic X-ray intensity (β:cps) of the main constituent element of the inorganic compound constituting the porous carrier for each pixel.

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.

An object of the present invention is to provide means for releasing oxygen at a temperature lower than conventional means in an exhaust gas purification catalyst. A Ce—Zr composite oxide is provided, which has a crystallite diameter of 6.5 nm or less and a BET specific surface area of 90 m.sup.2/g or more.

The present invention provides an exhaust gas purification catalyst including a base material and a catalyst layer 20 that is arranged on the base material. The catalyst layer 20 includes a catalyst metal and a carrying material carrying the catalyst metal. The catalyst layer 20 satisfies below: (1) in a pore distribution curve measured by a mercury porosimeter, a peak for the largest pore volume exists within a range of a pore diameter equal to or more than 1 μm and not more than 10 μm; and (2) on an electron microscopy observation image (with a 1000-fold magnification) of a surface of the catalyst layer 20, when areas of a plurality of voids comprised in the electron microscopy observation image are respectively calculated, a standard deviation for the areas of the plurality of voids is not more than 30 μm.sup.2.

An automotive catalytic converter includes a three-way catalyst having Rh as the only precious metal configured as a front zone and a three-way catalyst having a mixture of Rh and Pd, Pt, or both configured as a rear zone, such that an exhaust gas from an internal combustion engine passes through the front zone before passing through the rear zone to minimize sulfur poisoning of the catalytic converter.

A system and method of pre-purification of a feed gas stream is provided that is particularly suitable for pre-purification of a feed air stream in cryogenic air separation unit. The disclosed pre-purification systems and methods are configured to remove substantially all of the hydrogen, carbon monoxide, water, and carbon dioxide impurities from a feed air stream and is particularly suitable for use in a high purity or ultra-high purity nitrogen plant. The pre-purification systems and methods preferably employ two or more separate layers of hopcalite catalyst with the successive layers of the hopcalite separated by a zeolite adsorbent layer that removes water and carbon dioxide produced in the hopcalite layers.

The invention provides an oxygen storage material having high oxygen storage capacity and high thermal durability. The oxygen storage material of the invention has some of the La sites of La.sub.2CuO.sub.4 with a K.sub.2NiF.sub.4-type crystal structure replaced by Ce. The oxygen storage material may have the composition La.sub.(2.00-x)Ce.sub.xCuO.sub.4 (0.20≥×>0.00). The oxygen storage material may also have a precious metal supported. The precious metal may be Pt, Pd or Rh. The exhaust gas purification catalyst is an exhaust gas purification catalyst comprising an oxygen storage material according to the invention.