摘要:
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.
摘要:
The object of the present invention is to provide a method for producing an α,β-unsaturated carboxylic acid in higher selectivity. The present invention resides in a method for producing an α,β-unsaturated carboxylic acid from an olefin or an α,β-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.
摘要:
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 Å or more are useful as raw materials of a palladium catalyst for use in an α,β-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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
The present invention provides a method for producing an α,β-unsaturated carboxylic acid in high yield. In particular, the present invention resides in a method for producing an α,β-unsaturated carboxylic acid by oxidation of an olefin or an α,β-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.