Mitsubishi Rayon Company, Limited

Dia-nitrix Co., Ltd.

Hirokazu Watanabe

Kenichi Miyaki

Motoo Yanagita

Takashi Karasuda

Yutaka Sasaki

Kunio Mori

Kazufumi Nishida

The invention relates to a method for producing acrylonitrile which includes a vapor phase catalytic ammoxidation process of performing vapor phase catalytic ammoxidation by bringing a source gas containing propylene, molecular oxygen, and ammonia into contact with a fluidized bed catalyst to obtain acrylonitrile. The method is characterized in that the fluidized bed catalyst is a catalyst containing molybdenum and bismuth and the vapor phase catalytic ammoxidation process is performed while maintaining an adsorbed amount of ammonia per specific surface area (m/g) of the fluidized bed catalyst in the range of 0.05 to 0.6 &#x3bc;mol/m. According to the method for producing acrylonitrile of the invention, it is possible to stably maintain a high acrylonitrile yield over a long period of time.

Method for producing acrylonitrile

The invention relates to a method for producing acrylonitrile which includes a vapor phase catalytic ammoxidation process of performing vapor phase catalytic ammoxidation by bringing a source gas containing propylene, molecular oxygen, and ammonia into contact with a fluidized bed catalyst to obtain acrylonitrile. The method is characterized in that the fluidized bed catalyst consists of particles containing Fe, Sb, and Te, and the vapor phase catalytic ammoxidation process is performed while maintaining a B/A in the range of 2.0 to 5.0, where A denotes an atomic ratio of Te/Sb in a bulk composition of the fluidized bed catalyst and B denotes an atomic ratio of Te/Sb in a surface composition of the particles of the fluidized bed catalyst. According to the method for producing acrylonitrile of the invention, it is possible to stably maintain a high acrylonitrile yield over a long period of time.

The invention relates to a method for producing acrylonitrile which includes a vapor phase catalytic ammoxidation process of performing vapor phase catalytic ammoxidation by bringing a source gas containing propylene, molecular oxygen, and ammonia into contact with a fluidized bed catalyst to obtain acrylonitrile. The method is characterized in that the fluidized bed catalyst is a catalyst containing iron, antimony, and tellurium, and the vapor phase catalytic ammoxidation process is performed while maintaining an adsorbed amount of ammonia per specific surface area (m/g) of the fluidized bed catalyst in the range of 0.01 to 0.22 &#x3bc;mol/m. According to the method for producing acrylonitrile of the invention, it is possible to stably maintain a high acrylonitrile yield over a long period of time.

A process for producing a composite oxide catalyst which includes a step of preparing an aqueous slurry containing at least iron and antimony and composed of a liquid phase and a solid phase, a step of drying the aqueous slurry to obtain a dried material, and a step of calcining the obtained dried material, wherein of the precipitated particles having a particle size of not less than 1 &#x3bc;m but less than 150 &#x3bc;m contained within the aqueous slurry, the proportion of precipitated particles having a particle size of not less than 1 &#x3bc;m but less than 10 &#x3bc;m is within a range from 40 to 90% by volume, and the proportion of precipitated particles having a particle size of not less than 10 &#x3bc;m but less than 150 &#x3bc;m is within a range from 10 to 60% by volume.

Process for producing composite oxide catalyst

A catalyst for producing acrylonitrile capable of maintaining a high yield of acrylonitrile for a long time is provided. The catalyst has a composition represented by MoBiFeWRbABCDO(SiO), wherein A is Ni, Mg, Ca, Sr, Ba, Mn, Co, Cu, Zn, Cd or mixture thereof; B is Al, Cr, Ga, Y, In, La, Ce, Pr, Nd, Sm or mixture thereof; C is Ti, Zr, V, Nb, Ta, Ge, Sn, Pb, Sb, P, B, Te or mixture thereof; D is Ru, Rh, Pd, Re, Os, Ir, Pt, Ag or mixture thereof; SiOis silica, when a is 10, b is 0.1 to 1.5, c is 0.5 to 3.0, d is 0.01 to 2.0, e is 0.02 to 1.0, f is 2.0 to 9.0, g is 0 to 5, h is 0 to 3, i is 0 to 2, k is 10 to 200; and j is the atomic ratio of oxygen determined by the valence of other elements (excluding silicon); and (&#xd7;2+&#xd7;2)/(&#xd7;3+&#xd7;3+&#xd7;1+&#xd7;2+&#xd7;3) is 0.90 to 1.00.

Catalyst for producing acrylonitrile and process for producing acrylonitrile

A catalyst for synthesizing acrylonitrile that enables acrylonitrile to be synthesized at high yield, and a process for producing acrylonitrile using that catalyst, are provided. A catalyst for synthesizing acrylonitrile is used having a composition represented by FeSbCDTeFXYZO(SiO). In the formula, component C represents at least one element selected from the group consisting of Cu, Ni and Co, component D from the group consisting of Mo, W and V, component F from the group consisting of P and B, component X from the group consisting of Sn, Ti, Zr, Nb, Ta, Cr, Ru, Pd, Ag, Al, Ga, In, Tl, Ge, As, Bi, La, Ce, Pr, Nd and Sm, component Y from the group consisting of Mg, Ca, Sr, Ba, Mn, Zn and Pb, and component Z from the group consisting of Li, Na, K, Rb and Cs, and SiOrepresents silica, when a=10, b=5 to 60, c=0.1 to 8.0, d=0.1 to 4.0, e=0.1 to 5.0, f=1.3 to 5.0, x=0 to 5, y=0 to 5, z=0 to 2, h=10 to 200 and g is the atomic ratio of oxygen required to satisfy the valence of each of the elements excluding silicon, and f/d=1 to 5.

Catalyst for synthesizing acrylonitrile and process for producing acrylonitrile

A fluidized bed catalyst for producing acrylonitrile capable of maintaining a high yield of acrylonitrile over a long time, and a process for producing acrylonitrile using the catalyst are provided. A fluidized bed catalyst for producing acrylonitrile having a composition represented by a following general formula:MoBiFeWNiMgABCDEFGO(SiO)In the formula, A represents Ce and La, B represents Ca, Sr, Ba, Mn, Co, Cu, Zn and Cd, C represents Y, Pr, Nd, Sm, Al, Cr, Ga and In, D represents Ti, Zr, V, Nb, Ta, Ge, Sn, Pb and Sb, E represents Ru, Rh, Pd, Re, Os, Ir, Pt and Ag, F represents P, B and Te, G represents Li, Na, K, Rb, Cs and Tl, SiOrepresents silica, when a=10, b=0.1 to 1.5, c=0.5 to 3, d=0.1 to 1.5, e=0.1 to 8, f=0.1 to 5, g=0.1 to 1.5, h=0 to 8, i=0 to 3, j=0 to 3, k=0 to 3, l=0 to 3, m=0.01 to 2, p=10 to 200 and n is the atomic ratio of oxygen required to satisfy the valence of each of the elements excluding silicon, and (a&#xd7;2+d&#xd7;2)/(b&#xd7;3+c&#xd7;3+e&#xd7;2+f&#xd7;2+g&#xd7;3+h&#xd7;2+i&#xd7;3+m&#xd7;1)=0.90 to 1.00).

Fluidized bed catalyst for producing acrylonitrile and process for producing acrylonitrile

For the production of acrylonitrile by ammoxidation of propylene, there is provided a catalyst capable of giving a high yield for a long period of time. In producing acrylonitrile by ammoxidation of propylene, there is used a metal oxide as a catalyst, which metal oxide contains iron, antimony, molybdenum, bismuth, potassium, an F element, a G element, an H element and silica as essential components in a specific composition ratio, and in which metal oxide iron antimonate exists as a crystal phase, provided that the F element is at least one element selected from the group consisting of magnesium, calcium, strontium, barium, manganese, cobalt, nickel, copper, silver, zinc and cadmium, the G element is at least one element selected from the group consisting of chromium, aluminum, gallium and indium, and the H element is at least one element selected from the group consisting of yttrium, lanthanum, cerium, praseodymium, neodymium and samarium.

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Yokohama, Japan

Hirokazu Watanabe