关键词: 对苯二甲酸, 催化反应, 自由基, 添加剂

Abstract: The catalytic reaction mechanism of oxidation of p-xylene to terephthalic acid with Co-Mn-Br catalyst was presented，and the promotion and side effect of Br ions in oxidation of p-xylene was discussed. The research on promotion of oxidation of p-xylene by organic precursor to reduce the use of Br ions could alleviate corrosion of equipment and reduce the emission of bromide，realizing good economic and social benefits. A new practical application catalyst system for p-xylene oxidation was developed during the research on the promotion of oxidation reaction by a free-radical precursor by simulating the actual production of terephthalic acid (PTA) with p-xylene (PX) and intermediate p-toluic acid (PT acid) as raw materials. The new catalyst passed industrial test. The results showed that adding 40 ×10?6 additive into the reaction system could keep the concentrations of Co and Mn unchanged and reduce the concentration of Br ions from 500 ×10?6 to 250 ×10?6.

Key words: terephthalic acid, catalytic reaction, free radical, additive