Purification of Bioethanol by Ionic Liquid Additives in Distillation System

摘要

This study examined the potential use of ionic liquid (IL) as additives for the distillation of bioethanol from bioethanol-water mixture and applied an optimized distillation system to the purification of bioethanol from plant fermentation broths. Among the 9 ionic liquids addedto the distillation system, [OMIM][BF_4] has the greatest effect on the purification of ethanol from aqueous solutions. In addition, theamount of [OMIM][BF4], the initial concentration of ethanol in the mixture and the distillate fractions in the distillation system werestudied systematically. Under the optimization distillation system using 2 g of [OMIM][BF4], 20 mL of a 99.4 % (ethanol, v:v) aqueoussolution was distilled from 100 mL of a 20 % (bioethanol, v:v) bioethanol-water mixture and the boiling point (71 °C) was lower than thatof the bioethanol-water azeotrope.