Optimization and Economic Evaluation of Bioethanol Recovery and Purification Processes involving Extractive Distillation and Pressure Swing Adsorption

Abstract Biofuels are an attractive source of renewable energy as they can easily replace liquid fuels used in transportation and other machinery. The present study considers typical feed of ethanol-water-CO 2 from which ethanol is recovered and purified using two popular techniques: pressure swing adsorption with molecular sieves and extractive distillation using ethylene glycol. Heat integration in both processes is performed to ensure a fair basis for evaluation. Optimal separation cost is found to be US$0.1394/kg and US$0.1185/kg for the extractive distillation and pressure swing adsorption process, respectively. Hence, fuel-grade ethanol production via pressure swing adsorption with 15% lower separation cost is better than extractive distillation using ethylene glycol.