邻二甲苯空气液相氧化制取邻甲基苯甲酸的研究

Direct Preparing O-toluic Acid from O-xylene by Air Oxidation in Liquid Phase

探索采用单一变价的有机钴酸盐为催化剂 ,用空气直接氧化邻二甲苯制取邻甲基苯甲酸的过程及基本反应原理。实验采用kg级的塔式间歇反应实验装置 ,邻二甲苯一次投料量为 4 0kg ,邻二甲苯的单程转化率达到 6 0 %以上 ,目的产物的质量收率达到70 %。采用正交设计法实验 ,筛选出工艺过程的最佳操作条件 :温度 :180± 10℃ ,压力 :0 8MPa ,反应时间 :3 0h,尾气流量为 :6m3 /h。

This paper probes the principle and the process of direct preparing o-toluic acid from o-xylene over the single valence organic cobalt by the air oxidation in the liquid phase A kg-class tower batch reactor is applied,the experiment is carried out with the every batch of o-xylene 4 0 kg.Results show that the simple-pass conversion of o-xylene is over 60% and the yield of the aimed production is 70 wt%.Based on the orthogonal design the optimal production process condition is screenedi.e the reaction temperature is 180±10℃,the pressure is 0.8 MPa,the reaction time is 3.0 h and the exit gas velocity is 6 m 3/h.