Asahi Kasei Kogyo Kabushiki Kaisha

Asahi Kasei Kabushiki Kaisha

Asahi Kasei Chemicals Corporation

Satoru Komada

Hidenori Hinago

Mamoru Watanabe

Masatoshi Kaneta

Kazuyuki Hamada

Osamu Nagano

Kunitoshi Aoki

Eri Tateno

Sadao Shoji

It is an object to provide a novel oxide catalyst for producing an unsaturated acid or unsaturated nitrile by which reaction results are good and a high yield can be stably maintained for a prolonged period of time, a process for producing the oxide catalyst, and a process for producing an unsaturated acid or unsaturated nitrile using the oxide catalyst. According to the present invention, there is provided an oxide catalyst represented by following compositional formula (1):MoVSbNbMnWYO&#x2003;&#x2003;(1)wherein Y represents at least one element selected from alkaline earth metals and rare earth metals; a, b, c, d, e, f, and n each represents an atomic ratio based on one atom of Mo; 0.1&#x2266;a&#x2266;1, 0.01&#x2266;b&#x2266;1, 0.01&#x2266;c&#x2266;1, 0&#x2266;d&#x2266;0.1, 0&#x2266;e&#x2266;0.1, 0&#x3c;(d+e)&#x2266;0.1, 0&#x2266;f&#x2266;1; and n is a number determined by valencies of the constituent metals.

Catalyst for oxidation or ammoxidation, and process for producing the same

Disclosed is a catalyst for use in catalytic oxidation or ammoxidation of propane or isobutane in the gaseous phase, which comprises an oxide containing, in specific atomic ratios, molybdenum (Mo), vanadium (V), niobium (Nb) and antimony (Sb), wherein the oxide catalyst has a reduction ratio of from 8 to 12% and a specific surface area of from 5 to 30 m/g. Also disclosed is a process for efficiently producing this catalyst.

Catalyst for oxidation or ammoxidation

Disclosed is an oxide catalyst comprising an oxide represented by the formula MoVNbXYZQO(wherein: X is at least one element selected from the group consisting of Te and Sb; Y is at least one element selected from the group consisting of Al and W; Z is at least one element selected from the group consisting of elements which individually form an oxide having a rutile structure and a Z oxide having a rutile structure is used as a source of Z for producing the catalyst; Q is at least one element selected from the group consisting of titanium, tin, germanium, lead, tantalum, ruthenium, rhenium, rhodium, iridium, platinum, chromium, manganese, technetium, osmium, iron, arsenic, cerium, cobalt, magnesium, nickel and zinc, and a Q compound not having a rutile structure is used as a source of Q for producing the catalyst; and a, b, c, d, e, f and n are, respectively, the atomic ratios of V, Nb, X, Y, Z, Q and O, relative to Mo). Also disclosed is a process for producing an unsaturated carboxylic acid or an unsaturated nitrile by using the above-mentioned oxide catalyst.

Catalyst for use in catalytic oxidation or ammoxidation of propane or isobutane in the gaseous phase

Disclosed is a process for producing acrylonitrile from propylene, or methacrylonitrile from isobutylene by ammoxidation using an improved catalyst composition comprising an oxide catalyst represented by the formula: Mo,Bi,Fe,Ni,Q,A,E,O,, wherein Q is a mixture of chromium and indium, A is at least one element selected from potassium, rubidium and cesium, E is at least one element selected from manganese magnesium, zinc, cerium, sodium and phosphorus, and m is a number of from 10 to 14, b is a number of from 0.1 to 3, f is a number of from 0.1 to 3, n is a number of from 4 to 10, q is a number of from 0.1 to 2, a is a number of from 0.01 to 0.5, e is a number of from 0 to 3, and x is a number determined by the valence requirements of the other elements present, and a silica carrier having the oxide catalyst supported thereon, wherein the silica carrier is present in an amount of from 40 to 60% by weight, based on the total weight of the oxide catalyst and the silica carrier. With the oxide catalyst composition of the present invention, the desired acrylonitrile or methacrylonitrile can be produced in high yield.

Process for producing acrylonitrile or methacrylonitrile

An ammoxidation catalyst for use in producing acrylonitrile or methacrylonitrile from propane or isobutane, which comprises a compound oxide and a silica carrier having supported thereon the compound oxide, wherein the compound oxide comprises molybdenum, vanadium, niobium and at least one element selected from the group consisting of tellurium and antimony, and wherein the alkali metal content of the ammoxidation catalyst is extremely small or substantially zero, and a process for producing acrylonitrile or methacrylonitrile by using the ammoxidation catalyst. By the use of the ammoxidation catalyst of the present invention, acrylonitrile or methacrylonitrile can be produced in high yield, as compared to the yield achieved by conventional ammoxidation catalysts containing a silica carrier.

Ammoxidation catalyst for use in producing acrylonitrile or

An ammoxidation catalyst comprising a compound oxide of Mo, V, Nb, and at least one element selected from the group consisting of Te and Sb, wherein the compound catalyst exhibits an X-ray diffraction pattern satisfying the following relationship:

An ammoxidation catalyst comprising a compound oxide which contains, in specific atomic ratios, molybdenum; vanadium; niobium; at least one element selected from tellurium and antimony; and at least one element selected from ytterbium, dysprosium, erbium, neodymium, samarium, lanthanum, praseodymium, europium, gadolinium, terbium, holmium, thulium, lutetium and scandium. By the use of the ammoxidation catalyst of the present invention, the ammonia-based yield of acrylonitrile or methacrylonitrile can be largely increased without sacrificing the propane- or isobutane-based yield of acrylonitrile or methacrylonitrile. Thus, the feed-stock ammonia can be efficiently utilized in the ammoxidation of propane or isobutane while achieving an efficient utilization of propane or isobutane.

Disclosed is a niobium(Nb)-containing aqueous solution for use in producing a Nb-containing oxide catalyst, wherein the oxide catalyst comprises an oxide of a plurality of active component elements including Nb and is for use in a catalytic oxidation or ammoxidation of propane or isobutane in the gaseous phase, and wherein the oxide catalyst is prepared by a process comprising mixing the Nb-containing aqueous solution with (an) aqueous mixture(s) containing compounds of active component elements of the oxide catalyst other than Nb, to thereby provide an aqueous compound mixture, and drying the aqueous compound mixture, followed by calcination. The Nb-containing aqueous solution comprises water having dissolved therein a dicarboxylic acid, an Nb compound and optionally ammonia, wherein the dicarboxylic acid/Nb molar ratio (.alpha.) satisfies: 1.ltoreq.(.alpha.).ltoreq.4, and the ammonia/Nb molar ratio (.beta.) satisfies: 0.ltoreq.(.beta.).ltoreq.2. By the use of the niobium-containing aqueous solution, it has become possible to produce efficiently an oxide catalyst which, when used in a catalytic oxidation or ammoxidation of propane or isobutane in the gaseous phase, exhibits high catalytic activity, and which, therefore, can be advantageously used for producing (meth)acrylic acid or (meth)acrylonitrile in high yield.

Niobium-containing aqueous solution for use in producing

A process for producing acrylonitrile or methacrylonitrile from propane or isobutane by ammoxidation, which comprises reacting propane or isobutane with ammonia and molecular oxygen in the gaseous phase in a fluidized-bed reactor containing a catalyst comprising a compound oxide and a silica carrier having supported thereon the compound oxide, wherein the compound oxide contains molybdenum (Mo), tellurium (Te), vanadium (V) and niobium (Nb), and wherein the reaction is performed with an addition of a catalyst activator comprising at least one tellurium compound and optionally at least one molybdenum compound into the reactor. The process of the present invention is advantageous in that the catalytic activity of the catalyst is surely maintained at a high level even without replacing the catalyst with a fresh one by interrupting the ammoxidation reaction, so that production of acrylonitrile or methacrylonitrile by the ammoxidation of propane or isobutane can be stably performed for a prolonged period of time while maintaining a high yield of acrylonitrile or methacrylonitrile.

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Yokohama, Japan

Satoru Komada