Improvements on anhydrous ethanol production by extractive distillation using ionic liquid as solvent

Abstract

Biorefineries use a variety of separation methods in order to produce high value co-products from different feed streams. The ionic liquids (IL) represent new classes of non-volatile selective solvents with large solubility, low solution viscosities, low toxicity. In this work, a computational study on extractive distillation using ionic liquids aiming to improve the properties of separation and lower energy consumption compared to conventional extraction agents, showing significant potential for this application, was developed. The ternary vapor liquid equilibrium data were taken from literature and the process was modeled and simulated using Aspen Plus TM process simulation environment. Computed results showed that 1-Butyl-3-methylimidazolium methyl sulfate ([emim][mSO4]) consumes lesser energy per kilogram of anhydrous ethanol, obtaining an ethanol purity of 0.995 (in mass) and an ethanol percentage recovery of 99.9 wt%. © 2012 Published by Elsevier Ltd.