Patent ID: 7563927
Filing Date: 2009-07-21
Classification: C07C

Abstract:
1. In a method of producing (meth)acrolein or (meth)acrylic acid comprising the gas phase catalytic oxidation of at least one substance selected from the group consisting of propylene, propane, and isobutylene in the presence of molecular oxygen or a gas containing molecular oxygen in a fixed bed multi-tubular reactor having a plurality of reaction tubes, wherein the reaction tubes are filled with at least one catalyst and the reaction temperature is controlled by a heat medium flowing outside of the reaction tubes, the improvement comprising: (1) said at least one catalyst is a Mo—Bi-based composite oxide catalyst, (2) at the beginning of the reaction process, the temperature difference between a temperature of the heat medium and a peak temperature of the catalyst is set in the range of 20 to 80° C., and (3) during the reaction process, a peak temperature T (° C.) of the catalyst in the tube axis direction of the reaction tubes satisfies Equation 1 below: where L is the length of a reaction tube, T