Sustainable design and multi-objective optimization of eco-efficient extractive distillation with single and double entrainer(s) for separating the ternary azeotropic mixture tetrahydrofuran/ethanol/methanol

Abstract

Sustainable process for the separation of ternary azeotropic mixture tetrahydrofuran/ethanol/methanol should be developed to recycle value-added organic components and protect environment. Thereby, in this work, we propose an approach to develop a sustainable process for the recovery of these valuable compounds from their ternary azeotropic mixture. The suitable entrainers of direct and indirect extractive distillation processes are firstly screened via the thermodynamic insights (e.g., volatility line). Next, the separation sequence for the developed extractive distillation processes is determined by combining the residue curve maps, volatility order, and Lever rule. Then, the multi-objective particle swarm optimization algorithm is employed to obtain the established processes with optimal operating parameters via the integration of Matlab and Aspen Plus. Eventually, four indexes include total annual cost, CO2 emissions, process route index, and thermodynamic efficiency, which are used to assess the economic, environmental, safety, and energy efficiency performances. Relative to the indirect process, the direct extractive distillation sequence, in particular, provides 15.61%, 9.75%, and 48.4% reduction in total annual cost, CO2 emission, and inherent safety, respectively, while it improves the energy efficiency by 29.7%.