Abstract: 1,2,3-trimethylbenzene-indane system in the C₉ arene mixture has difficulty in separation due to their close boiling point. Purification of 1,2,3-trimethylbenzene was carried out by extractive distillation with sulfolane. Aspen Plus software was employed to simulate the extractive distillation process. The simulated values matched well with the experimental data, and their deviations were all less than 5%. The effects of theoretical tray, solvent ratio, reflux ratio and feeding location of the C₉ arene and solvent on the separation were investigated during the extractive distillation experiments and the Aspen process simulation. The results showed that under the optimized process parameters of the theoretical tray of 60—65, solvent ratio of 5—7, reflux ratio of 3—4, C₉ feeding location of No. 34—36 tray and solvent feeding location of No.8—10 tray, the high-purity 1,2,3-trimethylbenzene product can be obtained at overhead, and the mass fraction and yield can reach above 99% and 93%, respectively.

Key words: sulfolane, 1,2,3-trimethylbenzene, extractive distillation, simulation, optimization

摘要： 针对混合C₉芳烃原料中沸点接近、分离困难的连三甲苯-茚满物系，以环丁砜为萃取剂进行了萃取精馏分离提纯实验，并采用Aspen Plus化工流程模拟软件对萃取精馏工艺过程进行了模拟研究，萃取精馏实验数据与模拟结果吻合较好，相对偏差小于5%。结合萃取精馏实验和流程模拟考察了萃取精馏塔的理论塔板数、溶剂比（萃取剂与原料的质量比）、回流比以及原料和萃取剂的进料位置等因素对分离效果的影响规律。结果表明，环丁砜萃取精馏提纯连三甲苯较适宜的工艺条件是：萃取精馏塔的理论塔板数为60~65、溶剂比为5~7、回流比为3~4、原料的进料位置为第34~36块板、萃取剂的进料位置为第8~10块板，在此条件下，塔顶可获得高纯度的连三甲苯产品，其质量分数可达99%以上，回收率可达93%以上。

关键词: 环丁砜, 连三甲苯, 萃取精馏, 模拟, 优化