偏三甲苯液相异构化制均三甲苯

Synthesis of 1,3,5-Trimethylbenzene by Liquid Phase Isomerization of 1,2,4-Trimethylbenzene

提出了一种常压液相异构化生产均三甲苯的新工艺。该工艺所需设备简单,常压下操作,反应温度较低,同时副产均四甲苯。将异构化产物用丙烯烷基化后可将未反应的偏三甲苯转化为5-异丙基偏三甲苯。后者沸点比均三甲苯沸点高58℃,很易用蒸馏法分离得到98％以上的均三甲苯。中试证明,该工艺能耗低,可使生产成本降低,有较好的经济效益。

This artical presents a new process for production of 1, 3, 5-trimethylbenzene from 1,2, 4-trimethylbenzene by liquid-phase isomerization under ordinary pressure. This process needs only simple equipment. The reaction temperature is low and no catalytic hydrogen is required in the process. Durene is simultaneously produced as a by-product. After alkylation of the isomers with propene, the unreacted 1, 2, 4-trimethylbenzene is converted into 5-isopropyl-1, 2, 4-trimethylbenzene. The latter's boiling point is 58℃ higher than that of 1, 3, 5-trimethylbenzene and can be easily separated by distillation with a purity higher than 98% byweight. Pilot plant experiment results show that the process has lower energy consumption and production cost and better economic benefit.