Ethanol dehydration by extractive distillation

Abstract Experiments and process simulation enable favourable operating conditions to be determined for the extractive distillation of ethanol—water, with ethylene glycol as a solvent. The solvent molar rate to feed molar rate ratio S/F = 0·6 and the reflux ratio R = 0·5 were determined in order to achieve at least 99·5 mole % purity of ethanol. Other parameters examined include feed concentration, purity of solvent, and number of plates. Extractive distillation can be used to achieve high purity of ethanol at low energy consumption and under simple operating conditions.