Catalysts for oxidative esterification can be used, for example, fro converting (meth)acrolein to methyl (meth)acrylate. The catalysts are especially notable for high mechanical and chemical stability even over very long time periods, including activity and/or selectivity relatively in continuous operation in media having even a small water content.

Catalysts for oxidative esterification can be used, for example, fro converting (meth)acrolein to methyl (meth)acrylate. The catalysts are especially notable for high mechanical and chemical stability even over very long time periods, including activity and/or selectivity relatively in continuous operation in media having even a small water content.

A method for preparing a molybdenum-bismuth-based composite metal oxide.

A method for preparing a molybdenum-bismuth-based composite metal oxide.

The present invention provides a method for producing a catalyst for ammoxidation, comprising steps of: preparing a catalyst precursor slurry comprising a liquid phase and a solid phase; drying the catalyst precursor slurry to obtain dry a particle; and calcining the dry particle to obtain a catalyst for ammoxidation, wherein the solid phase of the catalyst precursor slurry comprises an aggregate containing a metal and a carrier, metal primary particles constituting the aggregate have a particle size of 1 μm or smaller, and an average particle size of the metal primary particles is 40 nm or larger and 200 nm or smaller.

The present invention provides a method for producing a catalyst for ammoxidation, comprising steps of: preparing a catalyst precursor slurry comprising a liquid phase and a solid phase; drying the catalyst precursor slurry to obtain dry a particle; and calcining the dry particle to obtain a catalyst for ammoxidation, wherein the solid phase of the catalyst precursor slurry comprises an aggregate containing a metal and a carrier, metal primary particles constituting the aggregate have a particle size of 1 μm or smaller, and an average particle size of the metal primary particles is 40 nm or larger and 200 nm or smaller.

Methods of synthesizing Bi.sub.2S.sub.3—CdS particles in the form of spheres as well as properties of these Bi.sub.2S.sub.3—CdS particles are described. Methods of photocatalytic degradation of organic pollutants employing these Bi.sub.2S.sub.3—CdS particles and methods of preventing or reducing microbial growth on a surface by applying these Bi.sub.2S.sub.3—CdS particles in the form of a solution or an antimicrobial product onto the surface are also specified.

A catalyst containing, as an essential component, molybdenum; bismuth; and cobalt, in which a sum (S) of ratios of peak intensities expressed by the following formula in an X-ray diffraction pattern obtained by using CuKα rays as an X-ray source is 42 or more and 113 or less.

S={(peak intensity at 2θ=14.1°±0.1°+(peak intensity at 2θ=25.4°±0.1°)+(peak intensity at 2θ=28.5°±0.1°)}/(peak intensity at 2θ=26.5°±0.1°)×100

A catalyst containing, as an essential component, molybdenum; bismuth; and cobalt, in which a sum (S) of ratios of peak intensities expressed by the following formula in an X-ray diffraction pattern obtained by using CuKα rays as an X-ray source is 42 or more and 113 or less.

S={(peak intensity at 2θ=14.1°±0.1°+(peak intensity at 2θ=25.4°±0.1°)+(peak intensity at 2θ=28.5°±0.1°)}/(peak intensity at 2θ=26.5°±0.1°)×100

A catalyst containing, as an essential component, molybdenum; bismuth; and cobalt, in which, with respect to a peak intensity at 2θ=25.3°±0.2° in an X-ray diffraction pattern obtained by using CuKα rays as an X-ray source, a changing rate (Q1) per 1000 hours of reaction time represented by the following formulae (1) to (4) is 16 or less.

Q1={(U1/F1−1)×100}/T×1000  (1)

F1=(peak intensity of catalyst before oxidation reaction at 2θ=25.3°±)0.2°/(peak intensity of catalyst before oxidation reaction at 2θ=26.5°±0.2°)×100  (2)

U1=(peak intensity of catalyst after oxidation reaction at 2θ=25.3°±0.2°)/(peak intensity of catalyst after oxidation reaction at 2θ=26.5°±0.2°)×100  (3)

T=time (hr) during which oxidation reaction is carried out  (4)