The present invention pertains to a catalyst for use in the selective catalytic reduction (SCR) of nitrogen oxides comprising: • a monolithic substrate and • a coating A which comprises an oxidic metal carrier comprising an oxide of titanium and a catalytic metal oxide which comprises an oxide of vanadium wherein the mass ratio vanadium/titanium is 0.07 to 0.26.

An object of the present invention is to provide a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutene, which enables a catalyst demonstrating favorable yield to be stably produced. According to the present invention, there is provided a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutane, comprising the steps of: (i) preparing a catalyst raw material mixture containing Mo, V and Nb and satisfying the relationships of 0.1≦a≦1 and 0.01≦b≦1 when atomic ratios of V and Nb to one atom of Mo are defined as a and b, respectively; (ii) drying the catalyst raw material mixture; and (iii) calcining a particle, in which a content of the particle having a particle diameter of 25 μm or less is 20% by mass or less and a mean particle diameter is from 35 to 70 μm, in an inert gas atmosphere.

An object of the present invention is to provide a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutene, which enables a catalyst demonstrating favorable yield to be stably produced. According to the present invention, there is provided a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutane, comprising the steps of: (i) preparing a catalyst raw material mixture containing Mo, V and Nb and satisfying the relationships of 0.1≦a≦1 and 0.01≦b≦1 when atomic ratios of V and Nb to one atom of Mo are defined as a and b, respectively; (ii) drying the catalyst raw material mixture; and (iii) calcining a particle, in which a content of the particle having a particle diameter of 25 μm or less is 20% by mass or less and a mean particle diameter is from 35 to 70 μm, in an inert gas atmosphere.

Provided are a preparation method for a propylene epoxidation catalyst, and a use thereof. During the preparation, an alkoxide solution of a prepared active component and a silica gel support are mixed, then a rotary evaporation treatment is performed on the mixture to remove a low-carbon alcohol to obtain a catalyst precursor, and then the obtained catalyst precursor is subjected to calcination and silylation treatments to obtain the propylene epoxidation catalyst. The catalyst is prepared in a simple process, can be applied to the chemical process of preparing propylene oxide by propylene epoxidation, has high average selectivity to propylene oxide, and has industrial application prospect.

Provided are a preparation method for a propylene epoxidation catalyst, and a use thereof. During the preparation, an alkoxide solution of a prepared active component and a silica gel support are mixed, then a rotary evaporation treatment is performed on the mixture to remove a low-carbon alcohol to obtain a catalyst precursor, and then the obtained catalyst precursor is subjected to calcination and silylation treatments to obtain the propylene epoxidation catalyst. The catalyst is prepared in a simple process, can be applied to the chemical process of preparing propylene oxide by propylene epoxidation, has high average selectivity to propylene oxide, and has industrial application prospect.

The present invention relates to a high-performance polyoxometalate catalyst and a method of preparing the same. More particularly, the present invention provides a high-performance polyoxometalate catalyst, the activity and selectivity of which may be improved by controlling the content of vanadium and the like and which has superior reproducibility and may unsaturated carboxylic acid from unsaturated aldehyde in a high yield for a long time, a method of preparing the same, and the like.

The present invention relates to a high-performance polyoxometalate catalyst and a method of preparing the same. More particularly, the present invention provides a high-performance polyoxometalate catalyst, the activity and selectivity of which may be improved by controlling the content of vanadium and the like and which has superior reproducibility and may unsaturated carboxylic acid from unsaturated aldehyde in a high yield for a long time, a method of preparing the same, and the like.

Provided is a catalyst structure which prevents an increase in pressure loss by a simple construction while the gas flow is efficiently stirred by a structure making contact between adjacent catalyst elements. The catalyst structure is provided with a first flat-plate part and a second flat-plate part which support, on surfaces thereof, a constituent having catalytic activity to an exhaust gas and face each other, and a stirring part which is provided in such a manner as to come into contact first with the first flat-plate part and the second flat-plate part in an extending manner from the first flat-plate part to the second flat-plate part at a prescribed angle with respect to the direction in which the exhaust gas flows.

Provided is a catalyst structure which prevents an increase in pressure loss by a simple construction while the gas flow is efficiently stirred by a structure making contact between adjacent catalyst elements. The catalyst structure is provided with a first flat-plate part and a second flat-plate part which support, on surfaces thereof, a constituent having catalytic activity to an exhaust gas and face each other, and a stirring part which is provided in such a manner as to come into contact first with the first flat-plate part and the second flat-plate part in an extending manner from the first flat-plate part to the second flat-plate part at a prescribed angle with respect to the direction in which the exhaust gas flows.

A photocatalytic functional film has a structure of a substrate, a barrier layer and a photocatalytic layer stacked one on another. The barrier layer is an amorphous TiO.sub.2 film, the photocatalyst layer comprises an amorphous TiO.sub.2 film, and particles of visible light responsive photocatalytic material formed on the surface of the amorphous TiO.sub.2 film. A method for producing a photocatalytic functional film includes: adding an alcohol solvent and an acid to a titanium precursor to obtain a TiO.sub.2 amorphous sol by dehydration and de-alcoholization reaction; applying and drying the TiO.sub.2 amorphous sol on a substrate to form a barrier layer; and applying and drying a composition formed by mixing particles of visible light responsive photocatalyst material with the TiO.sub.2 amorphous sol on the barrier layer, to form a photocatalyst layer.