Abstract: A method for regeneration of a molybdenum-containing oxide fluidized bed catalyst which comprises impregnating a fluidized catalyst of a metal oxide containing molybdenum, bismuth and iron which has been deteriorated by being used for a reaction in production of acrylonitrile by ammoxidation of propylene, with a solution of a molybdenum compound and a solution of at least one compound containing at least one element selected from the group consisting of iron, chromium, lanthanum and cerium which are prepared separately or with a previously prepared mixed solution of the above compounds, drying the resulting catalyst and, then, firing the catalyst at a temperature of 500-700° C.

Abstract: The present invention provides a process for preparing carbocyclic or heterocyclic nitrites by the vapor phase contact ammoxidation of carbocyclic compounds or heterocyclic compounds, in which the reaction is carried out effectively without the increase of the amount of ammonia or oxygen used or the introduction of steam to give the nitrites as the objective products stably with the passage of time in a high yield with a high selectivity.

Abstract: The present invention provides a process for preparing carbocyclic or heterocyclic nitrites by the vapor phase contact ammoxidation of carbocyclic compounds or heterocyclic compounds, in which the reaction is carried out effectively without the increase of the amount of ammonia or oxygen used or the introduction of steam to give the nitrites as the objective products stably with the passage of time in a high yield with a high selectivity.

Abstract: A process for conducting long-term ammoxidation of propylene in the presence of a metal oxide catalyst for ammoxidation of propylene at a temperature of from 300.degree. C. to 500.degree. C. to produce acrylonitrile and hydrogen cyanide, wherein in the process each of (A) elemental phosphorus or a phosphorus compound and (B) elemental tellurium or a tellurium compound is added as a regenerating agent at least once to the ammoxidation reaction system in accordance with the progress of the reaction, the regenerating agent (A) being added when the yields of both of acrylonitrile and hydrogen cyanide are reduced, and the regenerating agent (B) is chosen when the yield of acrylonitrile is reduced and the yield of hydrogen cyanide is unchanged or increased, to thereby maintain high levels of yields of acrylonitrile and hydrogen cyanide.

Abstract: A process for the production of antimony-containing metal oxide catalysts, comprising preparing a slurry containing as essential components an antimony component, a polyvalent metal compound, and silica sol, heating and drying the slurry to form a solid product, and then calcining the solid product, wherein the antimony component is a mixture of (A) at least one of antimonic acid, polyantimonic acid and the salts thereof and (B) antimony trioxide, and is prepared by mixing (A) and (B) in such a manner that the antimony provided by the (B) constitutes from 0.1 to 70 atomic % of the total amount of antimony and further in an aqueous slurry state. These antimony-containing metal oxide catalysts have superior activity and physical properties, and further reproducibility in the preparation thereof. Thus they are useful for production of aldehydes and acids through oxidation, nitriles through ammoxidation, and dienes, unsaturated aldehydes and unsaturated acids through oxidative dehydrogenation.

Abstract: A process for regenerating a deteriorated antimony containing oxide catalyst comprising as essential components of (i) antimony and (ii) at least one metal element selected from the group consisting of iron, cobalt, nickel, manganese, uranium, cerium, tin and copper wherein the antimony containing oxide catalyst is impregnated or sprayed with an aqueous solution of nitric acid and/or a nitrate, and the impregnated catalyst is dried, and then calcined at a temperature in the range of from 400.degree. to 1000.degree. C.

Abstract: A process for producing a catalyst comprising an antimony-containing oxide which comprises the steps of (A) calcining a mixture of metal oxides containing, as essential components, an oxide of antimony and an oxide of at least one metal selected from the group consisting of iron, cobalt, nickel, manganese, uranium, tin and copper, said calcining being at temperatures of from about 500.degree. C to about 1000.degree.