| 摘要 |
PURPOSE:To obtain terephthalic acid of purity usable for direct polymerization, by specifying the amounts of the respective catalyst components and method for feeding Br in oxidizing p-xylene in the liquid phase in the presence of a Co-Mn-Br based catalyst in acetic acid solvent. CONSTITUTION:p-Xylene is oxidized with oxygen or a gas containing oxygen, usually air in the liquid phase in the presence of a Co-Mn-Br based catalyst in an oxidation reactor at 190-230 deg.C under 10-50kg/cm<2> pressure to give terephthalic acid. In the process, the total amount of the metallic catalyst is 200- 2,000ppm peferably 400-1,500ppm based on the solvent, and the amount of Mn to be used is within 5-50wt%, preferably 8-30wt% range based on the total amount of the metal. Br in 1.5-6 times atomic ratio based on the Co metal is dispersed and fed to the feed port for the p-xylene and an outlet for the resultant slurry, and the feed rate thereof is (5/1)-(1/5), preferably (5/1)-(1/3) weight ratio. |
