METHOD FOR PRODUCING UNSATURATED ALDEHYDE AND UNSATURATED CARBOXYLIC ACID

摘要

Disclosed is a method wherein propylene, isobutylene or a tertiary butanol is catalytically oxidized with molecular oxygen in a vapor phase for producing corresponding unsaturated aldehyde and unsaturated carboxylic acid. This method enables to use a catalyst for a long time. Specifically disclosed is a method wherein propylene, isobutylene or a tertiary butanol as a raw material is catalytically oxidized with molecular oxygen in a vapor phase in the presence of a catalyst, which is composed of a complex oxide essentially containing molybdenum, bismuth and iron, for producing corresponding unsaturated aldehyde and unsaturated carboxylic acid. In this method, the reaction pressure and/or the molar ratio between oxygen and the raw material are controlled so that the reaction rate of the raw material is kept constant at a certain level within a temperature range of not less than (TA - 15)°C and not more than TA °C with TA °C being the boundary temperature of the activation energy of the catalyst.