Extractive distillation using ionic liquids-based mixed solvents combined with dividing wall column

Abstract

Abstract To further reduce the energy consumption, investment and operating costs of the extractive distillation (ED) process, this study focuses on the process intensification by the combination of ionic liquids-based mixed entrainers and dividing wall column (DWC) for methanol/ethanol/water separation process. Based on the process simulation results, energy efficiency, economic and environmental impact assessments were carried out and compared with the benchmarked ED process using ethylene glycol as entrainer. The ternary ED process using the ionic liquids-based mixed entrainer can reduce the total annual cost (TAC) by about 5.98% and the energy consumption by 2.93%. The TAC and energy consumption for the proposed ternary ED process with DWC using the ionic liquids-based mixed entrainer can be reduced by 7.81% and 4.52%, respectively. The novel ED process shows the high energy efficiency, low economy cost and low CO2 emissions with a great industrial application prospect when compared to the benchmarked process.