Separation of Tetrahydrofuran-Ethanol Azeotropic Mixture by Extractive Distillation

Abstract

Tetrahydrofuran and ethanol formed a minimum azeotrope and extractive distillation should be a suitable method to separate their mixture. In this work, a systematic study of the separation of tetrahydrofuran-ethanol mixture with an entrainer by extractive distillation was performed. In order to break the original binary azeotrope, ethylene glycol was chosen as the entrainer. Vapour-liquid equilibrium of tetrahydrofuran-ethanol-ethylene glycol system was determined experimentally and NRTL model was the best one to predict this system. The feasibility analysis of this process was validated by simulation through chemical process simulation software-Aspen Plus and the optimal operating conditions of the extractive distillation process were valuable for industrial applications. Simulation results were then corroborated in a batch experimental packing column. In both the simulation and experiments, tetrahydrofuran, whose purity is more than 99.5 %, was obtained respectively.