Patent ID: 11254634

Abstract:
Provided is a method for producing at least one of an unsaturated aldehyde and an unsaturated carboxylic acid from an alkene by an oxidation reaction, in which a n-layered catalyst layer (n≥2) is provided in a gas flow direction in a reaction tube, two or more kinds of catalysts having different activities are used; and the catalysts are packed in such a manner that dT≤20° C. is satisfied, when a difference between a temperature PTn of an exothermic peak in a n-th layer as counted from a gas inlet and a minimum value mTn−1 of a temperature of a catalyst layer which appears between an exothermic peak in a (n-1)th layer and an exothermic peak in a n-th layer from the gas inlet is represented as dT (=PTn−mTn−1), and the change rate of dT is 2.5 or less at a reaction bath temperature within a range of ±6° C. of a reaction bath temperature at which the highest yield is obtained.