Simulation and parametric study of the innovated process to purify bioethanol with ethylene oxide hydration as an auxiliary reaction

Abstract

By the conventional process, to purify bioethanol from fermentation reactor or bioreactor is relatively high cost, since the purity of bioethanol in the bioreactor output is very low (just around 8-14%) and there are azeotropes between bioethanol with water. Therefore, in the conventional process, a combination of distillation-adsorption, distillation-pervaporation, or extractive distillation is needed in order to get bioethanol with purity of 99.6% or above. In this research, an innovative process to purify bioethanol in a reactive distillation column with an auxiliary reaction of ethylene oxide hydration was proposed. The auxiliary reaction broke the water/bioethanol azeotrope. Impacts of the reflux ratio and the bottoms rate were investigated by simulating the process in Aspen Plus software. The results revealed that the innovated bioethanol purifying process theoretically could produce bioethanol with a purity of 99.9%.