An ammonia adsorption catalyst and a preparation method and a use thereof, where the ammonia adsorption catalyst includes a substrate and an adsorption layer located on the surface of the substrate, and the adsorption layer includes a noble metal-containing zeolite adsorption material. The catalyst has the advantages of high ammonia adsorption/conversion efficiency, low cost, and flexible application, etc.

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.

A NO.sub.x adsorber catalyst and its use in an emission treatment system for internal combustion engines, is disclosed. The NO.sub.x adsorber catalyst comprises a first layer consisting essentially of a support material, one or more platinum group metals disposed on the support material, and a NO.sub.x storage material.

A catalytic converter with excellent OSC performance and NO.sub.x purification performance. The converter includes a substrate with a cell structure through which exhaust gas flows, and a catalyst layer formed on a cell wall surface of the substrate. The catalyst layer includes a lower catalyst layer and an upper catalyst layer, the lower catalyst layer being formed on a surface of the substrate, and the upper catalyst layer being formed on a surface of the lower catalyst layer. The upper catalyst layer includes at least a zirconia support with rhodium carried thereon, and two types of ceria-zirconia-based composite oxides with different specific surface areas, each of the ceria-zirconia-based composite oxides having no rhodium carried thereon. The lower catalyst layer includes an alumina support with platinum carried thereon, and a ceria-zirconia-based composite oxide.

The object of the present invention is to provide an exhaust gas purifying catalyst that can achieve high purification performance while suppressing H.sub.2S emissions. The object is solved by an exhaust gas purifying catalyst in which the top layer of a catalyst coating layer comprises a ceria-zirconia composite oxide having a pyrochlore-type ordered array structure, in which the ceria-zirconia composite oxide contains at least one additional element selected from the group consisting of praseodymium, lanthanum, and yttrium at 0.5 to 5.0 mol % in relation to the total cation amount, and the molar ratio of (cerium+additional element):(zirconium) is within the range from 43:57 to 48:52.

Disclosed is an exhaust gas purification catalyst carrier which includes a phosphate salt represented by formula: MPO.sub.4 (wherein M represents Y, La, or Al) or a zirconium phosphate represented by formula ZrP.sub.2O.sub.7; an exhaust gas purification catalyst containing a noble metal at least containing Rh and supported on the carrier; and an exhaust gas purification catalyst product having a catalyst support made of a ceramic or metallic material, and a layer of the exhaust gas purification catalyst, the layer being supported on the catalyst support.

An exhaust gas purification device includes a substrate including an upstream end and a downstream end and having a length Ls; a first containing Pd particles, extending between the upstream end and a first position, and being in contact with the substrate; a second containing Rh particles, extending between the downstream end and a second position, and being in contact with the substrate; and a third catalyst layer containing Rh particles, extending between the upstream end and a third position, and being in contact with at least the first catalyst layer, wherein an average of a Rh particle size distribution is from 1.0 to 2.0 nm, and a standard deviation of the Rh particle size distribution is 0.8 nm or less in each of the second catalyst layer and the third catalyst layer.

Described are compositions and catalytic articles comprising both a first molecular sieve promoted with copper and a second molecular sieve promoted with iron, the first and second molecular sieves having a d6r unit and the first molecular sieves having cubic shaped crystals with an average crystal size of about 0.5 to about 2 microns. The weight ratio of the copper-promoted molecular sieve to the iron-promoted molecular sieve can be about 1:1 to about 4:1. The catalytic articles are useful in methods and systems to catalyze the reduction of nitrogen oxides in the presence of a reductant.

A lean gasoline exhaust treatment catalyst article is provided, the article comprising a catalytic material applied on a substrate, wherein the catalytic material comprises a first composition and a second composition, wherein the first and second compositions are present in a layered or zoned configuration, the first composition comprising palladium impregnated onto a porous refractory metal oxide material and rhodium impregnated onto a porous refractory metal oxide material; and the second composition comprising platinum impregnated onto a porous refractory metal oxide material. Methods of making and using such catalyst articles and the associated compositions and systems employing such catalyst articles are also described.

The invention discloses a core-shell structured catalyst comprising a core covered with a shell. The core is made of hematite, tourmaline, germanium, maifanite or kaolin. The invention also provides a method for preparing the catalyst including mixing raw materials of the core with water to form seed-balls with a particle size of 2-4 mm; mixing the seed-balls with raw materials of the shell and water, such that the seed-balls are covered with the raw materials of the shell to form pellets with a particle size of 3-5 mm; processing the pellets at 60-90° C. and then calcining to active the pellets at 450-550° C. to obtain a core-shell structured catalyst. The invention further discloses use of the core-shell structured catalyst in the ozone oxidation reaction. In the invention, a core-shell structured catalyst with good morphology and catalytic performance is prepared, and the production cost of the catalyst is reduced.