IE41329L - Catalyst, producing acrylonitrile. - Google Patents

Abstract

A process for producing acrylonitrile by reacting propylene with ammonia and oxygen in a fluidized bed reactor, in the presence of a catalyst containing oxides of molybdenum, bismuth, iron and phosphorus, supported on silica which is characterized by: (1) Preparing a slurry of catalyst raw material by using a silica sol phosphoric acid and molybdenum, bismuth, iron, and sodium in the form of their salts which are each soluble in water or nitric acid so as to obtain a catalyst having a composition mentioned below, and further so as to give 40% by weight or less of non-volatile solid matters in the slurry when dried in the subsequent step of spray drying; (2) spray-drying the resulting slurry at a temperature of 300degrees C or lower; (3) calcining the resultant powder at a temperature ranging from 650degrees C to 710degrees C and optionally pre-calcining it at a temperature ranging 250degrees C to 500degrees C, prior to said calcination; (4) thus obtaining a catalyst consisting of oxides of the elements of molybdenum, bismuth, iron and phosphorus and as a further added essential constituent, oxide of sodium, supported on 45-55% by weight of silica, and having the ratio of the constituents expressed by the general formula of Mo12BiaFebNacPd wherein the suffixed of a, b, c and d are atomic ratios of each of the elements relative to Mo12 and a is in the range of 4 to 6, b is in the range of 4 to 6, c is in the range of 1.1 to 6 and d is in the range of 0.5 to 1.5, and (5) fluidizing the catalyst obtained above by a stream of the mixed gas comprising propylene, ammonia and air in a ratio by volume of 1.0:1.0-1.3:9.0-11.0, at a contact time between 1 to 10 seconds, at a reaction temperature of 440-500degrees C and a reaction pressure of 0-1 kg/Cm2 (gauge). [IN143534A1]