The presently claimed invention provides a layered catalytic article and an exhaust system. The catalytic article comprises a first layer comprising platinum, a first platinum group metal component other than platinum, a ceria-alumina composite, and an oxygen storage component; wherein platinum is supported on the ceria-alumina component; the platinum group metal component is selected from palladium, rhodium or a combination thereof and the platinum group metal component is supported on the oxygen storage component; a second layer comprising a second platinum group metal component; and a refractory alumina component, an oxygen storage component or a combination thereof; wherein the second platinum group component is selected from platinum, palladium, rhodium or a combination thereof; and a substrate, wherein the amount of platinum is 10 to 80 wt. %, based on the total weight of platinum, palladium and rhodium. The presently claimed invention also provides a process for the preparation of a layered catalytic article and use of the catalytic article and the exhaust system for purifying a gaseous exhaust stream comprising hydrocarbons, carbon monoxide, and nitrogen oxides.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650° C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL/g and a BET surface area from 275 to 550 m.sup.2/g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

A catalyst may include a support and from 5 to 20 wt.-% of a promoter, based on the total weight of the catalyst, wherein the support may include titanium dioxide, zirconium dioxide, and/or a mixture thereof, and the promoter may be an alkali metal oxide. Processes for preparing such catalysts may include impregnating a support of titanium dioxide and/or zirconium dioxide with an aqueous solution including a preferably soluble alkali compound and calcining. Alkyl mercaptans may be prepared in the presence of such catalysts or catalysts obtained by such processes.

The present invention provides a tri-metallic layered catalytic article comprising a first layer comprising palladium supported on at least one of an oxygen storage component, and an alumina component; a second layer comprising platinum and rhodium, each supported on at least one of an oxygen storage component and a zirconia component; and a substrate, wherein the weight ratio of palladium to platinum is in the range of 1.0:0.4 to 1:2. The present invention also provides a process for preparing the tri-metallic layered catalytic article, an exhaust system for internal combustion engine and use of the tri-metallic layered catalytic article for purifying a gaseous exhaust stream.

A sintered body containing polycrystalline grains of a metal oxynitride containing at least two metal elements, wherein Ba and at least one metal element of a crystal phase of the sintered body are contained in a triple point that is not a void between the polycrystalline grains. A method for producing the sintered body includes sintering a mixture of at least a metal oxynitride as a main component and a sintering aid containing cyanamide in an atmosphere containing nitrogen or a rare gas or in a reduced-pressure atmosphere of 10 Pa or less while applying a mechanical pressure with a retention time at a maximum heating temperature during the sintering set to 1 minute to 10 minutes.

The present invention relates to a composite material including a porous titania thin film and a preparation method therefor. A composite material according to the present invention allows for a simple thin film formation process because of the use of cellulose crystals, makes it easy to control the structure of the titanium dioxide thin film provided therefor, has a large specific area, and is superior in terms of scratch resistance and photoactivity, thus finding useful applications in the various fields utilizing titanium dioxide as a photocatalyst.

A three-way catalyst article, and its use in an exhaust system for compressed natural gas engines, is disclosed. The catalyst article for treating exhaust gas from compressed natural gas (CNG) engine comprising: a substrate comprising an inlet end, an outlet end with an axial length L; a first catalytic region beginning at the outlet end and extending for less than the axial length L, wherein the first catalytic region comprises a first PGM component; and a second catalytic region beginning at the inlet end, wherein the second catalytic region comprises a second PGM component; wherein the first PGM component comprises palladium, platinum, or a combination thereof; and wherein the second PGM component comprises rhodium.

A catalyst, methods of making, and process of dehydrogenating paraffins utilizing the catalyst. The catalyst includes at least 20 mass % Zn, a catalyst support and a catalyst stabilizer. The catalyst is further characterizable by physical properties such as activity parameter measured under specified conditions. The catalyst may also be disposed on a porous support in an attrition-resistant form and used in a fluidized bed reactor.

The present invention relates to a mixed oxide composition based on zirconium and cerium, to the process for preparing it and to its use in the field of catalysis. The mixed oxide is characterized by a high specific surface area and a specific porosity after calcination at 1100° C.

The catalytic cracking catalyst contains a molecular sieve and an alumina substrate material. The alumina substrate material has a crystalline phase structure of γ-alumina. Based on the volume of pores with a diameter of 2-100 nm, the pore volume of the pores with a diameter of 2-5 nm accounts for 0-10%, the pore volume of the pores with a diameter of more than 5 nm and not more than 10 nm accounts for 10-25%, and the pore volume of the pores with a diameter of more than 10 nm and not more than 100 nm accounts for 65-90%.