초록 ▼

Process for regenerating a spent catalyst, which catalyst contains potassium, cobalt, nickel, iron, bismuth, phosphorus and molybdenum and sufficient oxygen to satisfy the valence of the other elements therein, on a support, e.g. silicon oxide, wherein at least a portion of the molybdenum has been l

Process for regenerating a spent catalyst, which catalyst contains potassium, cobalt, nickel, iron, bismuth, phosphorus and molybdenum and sufficient oxygen to satisfy the valence of the other elements therein, on a support, e.g. silicon oxide, wherein at least a portion of the molybdenum has been lost during ammoxidation, comprising impregnating said catalyst with bismuth and molybdenum in solution so that at least some of the molybdenum lost is replaced, e.g., a typical impregnating solution is prepared by dissolving molybdenum trioxide and phosphoric acid in water, adding nitric acid and finally dissolving bismuth nitrate pentahydrate in the resultant solution.

대표청구항 ▼

A process for regenerating a catalyst of the general formula AaBbCcFedBieMofOx wherein A is at least one element selected from the group consisting of an alkali metal, rare earth metal, tantalum and niobium, B is at least one element selected from the class consisting of nickel and cobalt, C is at l

A process for regenerating a catalyst of the general formula AaBbCcFedBieMofOx wherein A is at least one element selected from the group consisting of an alkali metal, rare earth metal, tantalum and niobium, B is at least one element selected from the class consisting of nickel and cobalt, C is at least one element selected frOm the class consisting of phosphorus and arsenic, “a”and “c”are numbers from 0 to 3, “b”is a number from 0.1 to 20, “d”is a number from 0.1 to 8, “e”is a number from 0.1 to 6, “f”is a number from 8 to 16, and “x”is a number determined by the valence requirements of the other elements present, wherein said catalyst has become at least partially deactivated by exposure to ammoxidation conditions which exposure is accompanied by the loss of a portion of the molybdenum originally present in the catalyst, which process comprises impregnating said catalyst with molybdenum and bismuth, separating the catalyst thus impregnated from any bismuth and molybdenum not absorbed by the catalyst and thereafter calcining the catalyst by heating the catalyst to a temperature in the range of about 300°-700°C in an oxidizing atmosphere to form a regenerated catalyst wherein the mole ratio of added molybdenum to bismuth is in the range 0.5-20 and at least 50% of the molydbenum lost is replaced. The process of claim 3 wherein an element selected from the class consisting of phosphorus, silicon and mixtures thereof are present in the solution. respectively, and wherein (x) is sufficient to satisfy the valence requirements of the other elements present and wherein said catalyst has lost from about 0.4 to about 1.2 moles of molybdenum as expressed in the above formula by exposure to ammoxidation, which comprises impregnating said catalyst with an aqueous solution comprising bismuth and molybdenum species until at least about 1.5 weight percent molybdenum and 0.56 weight percent bismuth, based upon the weight of the catalytic elements, is incorporated onto the surfaces of said catalyst, separating the catalyst thus treated from any solution not absorbed by the catalyst and thereafter calcining the catalyst by heating the catalyst to a temperature in The range of about 300°-700°C in an oxidizing atmosphere to obtain a regenerated catalyst.