甲基叔丁基醚萃取蒸馏脱硫的研究

Desulfurization of Methyl tert-Butyl Ether by Extractive Distillation

采用萃取蒸馏法将甲基叔丁基醚(MTBE)萃取到萃取剂中,蒸馏得到低硫MTBE产品,并对萃取剂及萃取蒸馏的操作条件进行了优化。实验结果表明,在水中添加非质子极性助溶剂ZRD制得的TMS萃取剂的脱硫效果较好,MTBE在TMS萃取剂中的溶解度为10.5。采用TMS萃取剂的最佳实验条件为:MTBE 50 m L、萃取温度15℃、TMS与MTBE的体积比3.0、萃取时间15 s、相分离时间7 min、蒸馏温度75℃、蒸馏时间25 min。在最佳实验条件下,MTBE的硫含量可从98.1μg/g降至8.4μg/g、脱硫率为91.44%、MTBE的质量收率为99.69%;TMS循环使用5次均可保证MTBE的硫含量降至10μg/g以下。该方法避免了因萃取剂硫含量富集而无法获得低硫MTBE产品的弊端。

The extractive distillation of methyl tert-butyl ether（MTBE） was investigated to obtain low-sulfur product. Extractants and operation conditions of the extractive distillation were optimized. The results showed that, the solubility of MTBE in TMS（H20 with cosolvent ZRD） was 10.5. Under the optimized conditions of TMS as extractant, extraction temperature 15 ℃, volume ratio of TMS to MTBE 3.0, extraction time 15 s, phase separation time 7 min, distillation temperature 75 ℃ and distillation time 25 min, the sulfur content in MTBE could be reduced from 98.1 μg/g to 8.4 μg/g, and the desulfurization rate and MTBE yield were 91.44% and 99.69%, respectively. The sulfur content was still reduced to less than 10 μg/g after TMS was reused 5 times. This method can avoid the enrichment of sulfur in extractants, which leads to that it is difficult to obtain low sulfur MTBE product.