Abstract: Disclosed is a method for producing a catalyst, in which physical properties of a dried material or a calcined material in a production process of the catalyst are stable and a change in at least one of a catalyst activity and a selectivity to a target product is small and hence reproducibility of the catalyst is excellent. The present invention is a method for producing a catalyst containing molybdenum, bismuth, and iron, which contains the steps of washing a surface of at least one device equipped in an apparatus for the production of catalyst, to which a solid matter adheres, with a basic solution, and producing the catalyst with the apparatus for the production of catalyst thus washed.

Abstract: Disclosed is a method for producing a catalyst, in which physical properties of a dried material or a calcined material in a production process of the catalyst are stable and a change in at least one of a catalyst activity and a selectivity to a target product is small and hence reproducibility of the catalyst is excellent. The present invention is a method for producing a catalyst containing molybdenum, bismuth, and iron, which contains the steps of washing a surface of at least one device equipped in an apparatus for the production of catalyst, to which a solid matter adheres, with a basic solution, and producing the catalyst with the apparatus for the production of catalyst thus washed.

Abstract: A method for producing an unsaturated aldehyde and an unsaturated carboxylic acid through gas-phase catalytic oxidation of propylene, isobutylene or tertiary butanol, which is a raw material, with molecular oxygen in the presence of a catalyst comprising a complex oxide including molybdenum, bismuth and iron as essential components, by controlling the molar ratio of oxygen to the raw material such that a rate of reaction of the raw material is kept constant in the temperature range of from (TA-15)° C. to TA° C., where TA° C. is the boundary temperature of the activation energy of the catalyst.

Abstract: A method for producing an unsaturated aldehyde and an unsaturated carboxylic acid through gas-phase catalytic oxidation of propylene, isobutylene or tertiary butanol, which is a raw material, with molecular oxygen in the presence of a catalyst comprising a complex oxide including molybdenum, bismuth and iron as essential components, by controlling the molar ratio of oxygen to the raw material such that a rate of reaction of the raw material is kept constant in the temperature range of from (TA—15)° C. to TA° C., where TA° C. is the boundary temperature of the activation energy of the catalyst.

Abstract: Disclosed is a method of a gas-phase catalytic oxidation reaction of propylene, isobutylene, or tertiary butanol with molecular oxygen in the presence of a catalyst to produce a corresponding unsaturated aldehyde and a corresponding unsaturated carboxylic acid, in which the catalyst can be used over a long period of time. Concretely, in the presence of the catalyst containing a complex oxide including molybdenum, bismuth and iron as essential components, at least one factor of a reaction pressure and a molar ratio of molecular oxygen to a raw material is controlled to change in such a way that a rate of reaction of the raw material is kept constant in the temperature range of from (TA?15)° C. to TA° C., when a boundary temperature of the activation energy of the catalyst is set to be TA° C.

Abstract: Disclosed is a method for producing at least one of an ?,?-unsaturated aldehyde and an ?,?-unsaturated carboxylic acid from an alcohol in a liquid phase through a simple process. Namely, at least one of an ?,?-unsaturated aldehyde and an ?,?-unsaturated carboxylic acid is produced by dehydrating and oxidizing an alcohol in a liquid phase at 110 to 250° C. in the presence of molecular oxygen and a noble metal-containing catalyst. Alternatively, at least one of an ?,?-unsaturated aldehyde and an ?,?-unsaturated carboxylic acid is produced by dehydrating and oxidizing an alcohol in a liquid phase in the presence of molecular oxygen, a noble metal-containing catalyst, and an acidic substance.

Abstract: Disclosed is a method for producing at least one of an ?,?-unsaturated aldehyde and an ?,?-unsaturated carboxylic acid from an alcohol in a liquid phase through a simple process. Namely, at least one of an ?,?-unsaturated aldehyde and an ?,?-unsaturated carboxylic acid is produced by dehydrating and oxidizing an alcohol in a liquid phase at 110 to 250° C. in the presence of molecular oxygen and a noble metal-containing catalyst. Alternatively, at least one of an ?,?-unsaturated aldehyde and an ?,?-unsaturated carboxylic acid is produced by dehydrating and oxidizing an alcohol in a liquid phase in the presence of molecular oxygen, a noble metal-containing catalyst, and an acidic substance.

Abstract: Disclosed is a method of a gas-phase catalytic oxidation reaction of propylene, isobutylene, or tertiary butanol with molecular oxygen in the presence of a catalyst to produce a corresponding unsaturated aldehyde and a corresponding unsaturated carboxylic acid, in which the catalyst can be used over a long period of time. Concretely, in the presence of the catalyst containing a complex oxide including molybdenum, bismuth and iron as essential components, at least one factor of a reaction pressure and a molar ratio of molecular oxygen to a raw material is controlled to change in such a way that a rate of reaction of the raw material is kept constant in the temperature range of from (TA-15)° C. to TA° C., when a boundary temperature of the activation energy of the catalyst is set to be TA° C.

Abstract: Disclosed is a method for producing a catalyst, in which physical properties of a dried material or a calcined material in a production process of the catalyst are stable and a change in at least one of a catalyst activity and a selectivity to a target product is small and hence reproducibility of the catalyst is excellent. The present invention is a method for producing a catalyst containing molybdenum, bismuth, and iron, which contains the steps of washing a surface of at least one device equipped in an apparatus for the production of catalyst, to which a solid matter adheres, with a basic solution, and producing the catalyst with the apparatus for the production of catalyst thus washed.

Abstract: The object of the present invention is to provide a method for producing an ?,?-unsaturated carboxylic acid in higher selectivity. The present invention resides in a method for producing an ?,?-unsaturated carboxylic acid from an olefin or an ?,?-unsaturated aldehyde in liquid phase by using a noble metal-containing catalyst and by causing a compound (A) having an acid dissociation exponent (pKa) of less than 4 to be present in the liquid phase.

Abstract: The method of producing a catalyst for synthesis of an unsaturated aldehyde and unsaturated carboxylic acid of the present invention is characterized in that the method comprises a step of adding liquid to particles containing molybdenum, bismuth and iron and kneading the mixture, and extrusion-molding this kneaded substance, a step of preserving the molded article obtained by extrusion molding, and at least one step of drying and calcining the preserved molded article, and the contact time of particles containing molybdenum, bismuth and iron with liquid is 1 to 48 hours, and the preserving time of the molded article is 50% or more of the contact time of particles containing molybdenum, bismuth and iron with liquid. According to the production method of the present invention, catalytic activity can be easily controlled, and a catalyst having high activity and high selectivity is obtained.

Abstract: The present invention provides a method for producing an ?,?-unsaturated carboxylic acid in high yield. In particular, the present invention resides in a method for producing an ?,?-unsaturated carboxylic acid by oxidation of an olefin or an ?,?-unsaturated aldehyde with molecular oxygen in liquid phase in the presence of a catalyst containing at least palladium, wherein at least one compound selected from the group consisting of p-methoxyphenol, 4,4?-dihydroxytetraphenylmethane, 1,1,1-tris(p-hydroxyphenyl)ethane, compounds having an N-oxyl group in the molecule and compounds having an N-nitrosyl group in the molecule is caused to be coexistent.

Abstract: The object of the present invention is to provide a method for producing an ?,?-unsaturated carboxylic acid in higher selectivity. The present invention resides in a method for producing an ?,?-unsaturated carboxylic acid from an olefin or an ?,?-unsaturated aldehyde in liquid phase by using a noble metal-containing catalyst and by causing a compound (A) having an acid dissociation exponent (pKa) of less than 4 to be present in the liquid phase.

Abstract: A carbon-insertion-type palladium metal in which an amount of inserted carbon is 0.16 mol or more with respect to 1.0 mol of a palladium metal, and a carbon-insertion-type palladium metal in which a crystal face distance of a (111) face of a palladium metal is 2.270 ? or more are useful as raw materials of a palladium catalyst for use in an ?,?-unsaturated carboxylic acid preparation reaction, and the like. The carbon-insertion-type palladium metal can preferably be prepared by reduction of palladium in a palladium compound having a chlorine content of 0 to 300 ppm.

Abstract: A catalyst for preparation of an ?,?-unsaturated carboxylic acid in which a precious metal is supported on activated carbon having a specific surface area of 100 m2/g or more and 1300 m2/g or less is a catalyst by which the ?,?-unsaturated carboxylic acid can be prepared from an olefin or ?,?-unsaturated aldehyde in a high yield. This catalyst can be prepared by selecting activated carbon having a specific surface area of 100 m2/g or more and 1300 m2/g or less and loading a precious metal on the activated carbon.

Abstract: Prepared is a catalyst for use in the production of an unsaturated aldehyde and an unsaturated carboxylic acid in which catalytic activity is high and selectivity is excellent by a preparation process containing the steps of preparing catalyst component particles as dried particles prepared by spray drying an aqueous slurry containing molybdenum, bismuth and iron or as calcined particles prepared by further heat treating the dried particles; mixing and kneading the catalyst component particles with at least a liquid; first-molding the kneaded material; and second-molding the first-molded product to a finished shape using a piston molding machine.

Abstract: In producing a catalyst used for synthesis of an unsaturated aldehyde and an unsaturated carboxylic acid by a gas-phase catalytic oxidation, there is used a step of packing an additive-containing catalyst precursor of the catalyst into a tubular reactor, passing a gas through the tubular reactor, and elevating, in this state, the temperature of the additive-containing catalyst precursor so that a temperature of the gas at an outlet of the catalyst precursor layer becomes higher than a temperature of the gas at an inlet of the catalyst precursor layer. The step makes possible easy and highly reproducible production of a high-performance catalyst which is small in the reduction in catalytic performance caused by, for example, the thermal decomposition of the additive contained in the catalyst precursor.

Abstract: A molybdenum-based precipitate is prepared according to a process including the first step of forming a crude precipitate by pH adjustment to 6.5 or less in the presence of an alkali metal compound, and the second step of dissolving the crude precipitate in aqueous ammonia and forming a precipitate by pH adjustment to 6.5 or less. Then, the resulting molybdenum-based precipitate is washed with an acid aqueous solution having a pH of 6.5 or less and containing not less than 0.01 mole/L of ammonium root. Thus, a change in average particle diameter can be suppressed and good workability can be achieved, so that a molybdenum-based precipitate having a high purity and a desired average particle diameter can be obtained.

Abstract: The method of producing a catalyst for synthesis of an unsaturated aldehyde and unsaturated carboxylic acid of the present invention is characterized in that the method comprises a step of adding liquid to particles containing molybdenum, bismuth and iron and kneading the mixture, and extrusion-molding this kneaded substance, a step of preserving the molded article obtained by extrusion molding, and at least one step of drying and calcining the preserved molded article, and the contact time of particles containing molybdenum, bismuth and iron with liquid is 1 to 48 hours, and the preserving time of the molded article is 50% or more of the contact time of particles containing molybdenum, bismuth and iron with liquid. According to the production method of the present invention, catalytic activity can be easily controlled, and a catalyst having high activity and high selectivity is obtained.

Abstract: The present invention relates to the effective utilization of a used catalyst containing at least molybdenum, an A element (at least one element selected from the group consisting of phosphorus and arsenic) and an X element (at least one element selected from the group consisting of potassium, rubidium and cesium), and provides a process for producing a catalyst, which comprises dispersing said used catalyst in water, adding thereto an alkali metal compound and/or ammonia solution, adjusting the resulting mixture to pH 6.5 or less to generate a precipitate containing at least molybdenum and the A element, and using the precipitate as a material for catalyst-constituting elements.