Oxidative dehydrogenation catalysts for converting lower paraffins to alkenes such as ethane to ethylene when prepared as an agglomeration, for example extruded with supports comprising slurries of Nb.sub.2O.sub.5.

The present invention clarifies the characteristic of the hygroscopicity of the catalyst for producing acrylic acid and finds out a relationship between the water amount of the catalyst and the catalytic performance as the catalyst for producing acrylic acid, and provides an excellent catalyst. Provided is a catalyst for producing acrylic acid, which contains molybdenum and vanadium as essential active components, in which the amount of water contained in the catalyst is 0.01 mass % or more and 0.53 mass % or less.

The present invention clarifies the characteristic of the hygroscopicity of the catalyst for producing acrylic acid and finds out a relationship between the water amount of the catalyst and the catalytic performance as the catalyst for producing acrylic acid, and provides an excellent catalyst. Provided is a catalyst for producing acrylic acid, which contains molybdenum and vanadium as essential active components, in which the amount of water contained in the catalyst is 0.01 mass % or more and 0.53 mass % or less.

Provided is a catalyst for producing an unsaturated carboxylic acid, in which a ratio of a diffraction line intensity of 2=19.10.3 with respect to a diffraction line intensity of 2=10.70.3 in X-ray diffraction measurement is 0.20 or more and less than 0.58, and the catalyst having an active component represented by formula (A) shown below:

Mo.sub.10V.sub.aP.sub.bCu.sub.cAs.sub.dX.sub.eO.sub.g(A)

Provided is a catalyst for producing an unsaturated carboxylic acid, in which a ratio of a diffraction line intensity of 2=19.10.3 with respect to a diffraction line intensity of 2=10.70.3 in X-ray diffraction measurement is 0.20 or more and less than 0.58, and the catalyst having an active component represented by formula (A) shown below:

Mo.sub.10V.sub.aP.sub.bCu.sub.cAs.sub.dX.sub.eO.sub.g(A)

A (methyl)acrolein oxidation catalyst and a preparation method therefor-in which the catalyst has a composition represented by the following formula: x(Mo12PaCsbVcDeOf)+tC/yZ in which Mo.sub.12P.sub.aCs.sub.bV.sub.cD.sub.eO.sub.f is a heteropolyacid salt main catalyst; C is a nano carbon fiber additive, and Z is a carrier thermal conduction diluent; Mo, P, Cs, V, and O represent the elements of molybdenum, phosphorus, cesium, vanadium, and oxygen, respectively; D represents at least one element selected from the group consisting of copper, iron, magnesium, manganese, antimony, zinc, tungsten, silicon, nickel, and palladium; a, b, c, e, and f represent the atomic ratio of each element, a=0.1-3, b=0.01-3, c=0.01-5, e=0.01-2, and f being the atomic ratio of oxygen required to satisfy the valence of each of the described components; x and y represent the weights of the main catalyst and the carrier thermal conduction diluent Z, and y/x=11.1-50%; and t represents the weight of the nano carbon fiber, and t/x=3-10%.

A (methyl)acrolein oxidation catalyst and a preparation method therefor-in which the catalyst has a composition represented by the following formula: x(Mo12PaCsbVcDeOf)+tC/yZ in which Mo.sub.12P.sub.aCs.sub.bV.sub.cD.sub.eO.sub.f is a heteropolyacid salt main catalyst; C is a nano carbon fiber additive, and Z is a carrier thermal conduction diluent; Mo, P, Cs, V, and O represent the elements of molybdenum, phosphorus, cesium, vanadium, and oxygen, respectively; D represents at least one element selected from the group consisting of copper, iron, magnesium, manganese, antimony, zinc, tungsten, silicon, nickel, and palladium; a, b, c, e, and f represent the atomic ratio of each element, a=0.1-3, b=0.01-3, c=0.01-5, e=0.01-2, and f being the atomic ratio of oxygen required to satisfy the valence of each of the described components; x and y represent the weights of the main catalyst and the carrier thermal conduction diluent Z, and y/x=11.1-50%; and t represents the weight of the nano carbon fiber, and t/x=3-10%.

The present invention provides a catalyst including Mo, Bi, and Fe, wherein P/R is 0.10 or less, wherein P is a peak intensity at 2=22.90.2 and R is a peak intensity at 2=26.60.2, in X-ray diffraction analysis.

The present invention provides a catalyst including Mo, Bi, and Fe, wherein P/R is 0.10 or less, wherein P is a peak intensity at 2=22.90.2 and R is a peak intensity at 2=26.60.2, in X-ray diffraction analysis.

A highly active quaternary mixed transition metal oxide material has been developed. The material may be sulfided to generate metal sulfides which are used as a catalyst in a conversion process such as hydroprocessing. The hydroprocessing may include hydrodenitrification, hydrodesulfurization, hydrodemetallation, hydrodesilication, hydrodearomatization, hydroisomerization, hydrotreating, hydrofining, and hydrocracking.