PRODUCTION OF AROMATIC CARBOXYLIC ACID

摘要

PURPOSE:To obtain the titled high-purity compound in oxidizing an aliphatic group-substituted aromatic compound in a liquid phase and crystallizing the reaction product, by setting a blending means in the midst a transportation pipe connecting a reactor to a crystallization tank and partially feeding crystal- containing slurry from the crystallization tank to the blending means. CONSTITUTION:In oxidizing an aliphatic group-substituted aromatic compound with O2 in a solvent in the presence of a derivative in a liquid phase in a reactor 1 of batch type, transporting the prepared reaction product containing an aromatic carboxylic acid to a crystallization tank 4 and crystallizing the aromatic carboxylic acid, slurry obtained in the crystallization tank 4 is partially sent from circulating piping 3C through a flow rate regulating valve 2 and blended with the solution of the reaction product in the midst of a transportation pipe 3b connecting the reactor 1 to the crystallization tank 4, transferred to the crystallization tank 4 and crystallized to give the high-purity carboxylic acid.