离子液体在回收模拟粗苯中噻吩的研究

Recovery of thiophen in simulative crude benzol by extraction with ionic liquid

为回收焦化粗苯中的噻吩,采用等物质的量的磷酸三甲酯和N-甲基咪唑反应合成离子液体,以该离子液体为萃取剂萃取脱除粗苯模拟液中的噻吩,并通过再生离子液体的方法回收噻吩。实验考察了萃取时间、萃取温度、离子液体与粗苯模拟液的体积比以及离子液体的重复使用性能等对噻吩脱除效率的影响,同时对萃取后离子液体中噻吩的回收也做了相应的探讨。结果表明:在萃取时间为30 min,萃取温度为40℃,离子液体与粗苯模拟液的体积比为1时,噻吩的脱除率达到最大值30.48%;同时离子液体作为萃取剂重复使用3次后脱硫性能显著下降。经过减压蒸馏再生后,离子液体的脱硫性能较之以前几乎保持不变,并且在再生的过程中可回收约66.20%的噻吩。

To recover thiophen in crude benzol, the ionic liquid was synthesized by the reaction of equimolar N-methylimidazole with trimethyl phosphate. The ionic liquid was used as extraction desulfurization agent to remove thiophen in simulative crude benzol, and the used ionic liquid was regenerated to recover thiophen. The effects of extraction time, extraction temperature, the volume ratio of ionic liquid to simulative crude benzol, the repetitive performance of the ionic liquid on the rate of thiophen removal from the simulative crude benzol were investigated, and the recovery of thiophen during the ionic liquid regeneration was discussed. The results show that optimal desulfurization conditions are 30 rain, 40 ℃ and V（ ionic liquid） ： V（ simulative crude benzene） = 1 ： 1, the sulfur removal is 30.48% ; the ionic liquid could be used repeatedly for 3 times. The used ionic liquids could be regenerated and about 66.20% of the thiophen is recovered during regeneration by vacuum distillation. After regeneration, the extraction desulfurization performance of the ionic liquid remains almost unchanged.