METHOD FOR PRODUCING (METH)ACRYLIC ACID OR (METH)ACROLEIN

摘要

An object of the present invention is to provide that, in a process for the production of (meth)acrolein or (meth)acrylic acid by a gas-phase catalytic oxidation reaction of a substance to be oxidized such as propylene, propane, isobutylene and (meth)acrolein with molecular oxygen or molecular oxygen-containing gas using a multi-tubular reactor equipped with one or more catalyst layer(s) in a direction of tube axis, a sudden rise of temperature is suppressed even after changing the reaction condition for raising the reaction temperature for enhancing the production velocity whereby inactivation of the catalyst is prevented and a stable production is carried out. The present invention relates to a process where a change in the reaction condition for raising the reaction temperature is conducted by changing the temperature of the heat medium for the adjustment of reaction temperature at the inlet equipped with the above-mentioned multi-tubular reactor and, at that time, (1) change in the inlet temperature of the heat medium is conducted at not higher than 2°C for each changing operation and (2) when another changing operation is continuously conducted, the changing operation is conducted where the time interval from the changing operation immediately before that is made not shorter than 10 minutes.