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

There is provided a method for producing isobutylene, in which isobutylene is produced from isobutanol with a high selectivity while suppressing a decrease in the isobutanol conversion rate under pressure. In the method for producing isobutylene according to the present invention, a raw material gas containing isobutanol is brought into contact with a catalyst to produce isobutylene from isobutanol, the method including bringing the raw material gas containing isobutanol into contact with a catalyst at a linear velocity of 1.20 cm/s or more under a pressure of 120 kPa or more in terms of absolute pressure to produce isobutylene from isobutanol.

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.

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)

A catalyst may suppress pressure loss and coaking and produce a target substance in high yield when a gas-phase catalytic oxidation reaction of a material substance is conducted using the catalyst to produce the target substance. A ring-shaped catalyst may have a straight body part and a hollow body part, which is used when a gas-phase catalytic oxidation reaction of a material substance is conducted to produce a target substance, wherein a length of the straight body part is shorter than a length of the hollow body part and at least at one end part, a region from an end part of the straight body part to an end part of the hollow body part is concavely curved.

There is provided an ammoxidation catalyst for propylene having a structure in which molybdenum (Mo) oxide is supported first, and an oxide of heterogeneous metals including bismuth (Bi) is supported later. Related methods of making and using the catalyst are also provided.

An object of the present invention is to provide a catalyst capable of improving the selectivity of unsaturated aldehydes and unsaturated carboxylic acids, and a catalyst containing molybdenum, antimony, bismuth, and iron, wherein an atom ratio of the antimony to the molybdenum on a surface of the catalyst is greater than an atom ratio of the antimony to the molybdenum in the entire catalyst is provided.

The present disclosure relates to an ammoxidation catalyst for propylene, a manufacturing method of the same, and an ammoxidation method of propylene using the same. Specifically, in one embodiment of the present disclosure, there is provided a catalyst having a structure in which a metal oxide is supported on a silica support having a narrow particle size distribution, and excellent wear resistance.

The present invention provides a method for producing 1,3-butadiene that is capable of suppressing generation of reaction by-products. The method includes: a step (A) of to obtain a produced gas containing 1,3-butadiene; a step (B) of cooling the produced gas; and a step (C) of separating the produced gas cooled in the step (B) into molecular oxygen and inert gases, and other gases containing 1,3-butadiene, by selective absorption into an absorption solvent. In the method, in the step (A), the raw material gas and a molecular oxygen-containing gas are supplied to a fixed-bed reactor with a composite oxide catalyst containing molybdenum and bismuth; the molar ratio of molecular oxygen to n-butene in the gases is 1.0 to 2.0; and the molar ratio of water vapor to n-butene in the gases supplied to the fixed-bed reactor is not more than 1.2.