Production of Anhydrous Ethanol by Extractive Distillation of Diluted Alcoholic Solutions with Ionic Liquids

摘要

In this work, the use of the ionic liquid l-methyl-3-methylimidazolium dimethylphosphate or ethylene glycol as an separation agent was evaluated in a two-column or three-column configuration extractive distillation for the production of anhydrous ethanol (99.8% weight, 99.5% mol) from diluted solutions (11% weight). The extractive distillation process was simulated and optimized with the HYSYS~R software. The vapor liquid equilibrium for the system was calculated by the NRTL thermodynamic model, whose interactions parameters were previously published. Experimental design was used in combination with modeling and simulation to determine the operational conditions that minimize reboiler duty. Simulation results showed that both separating agents present similar reboiler duty to produce high-purity ethanol.