Separation for diethoxymethane/ethanol/water by a thermally coupled extractive pressure swing distillation process with mixed solvent

Abstract

A sustainable and efficient process for separating diethoxymethane/ethanol/water azeotropic systems was proposed via a mixed solvent as an entrainer and thermal coupling technology to enhance the extractive distillation process. The microscopic mechanisms between different molecules were precisely explored through molecular simulation technology, and suitable candidate entrainers were determined. On this basis, extractive distillation processes using different solvents as entrainer were further designed. The operation parameters of the process were improved by multi-objective optimization. The extractive distillation process coupled with heat pump and heat integration technology was further brought in based on the optimal solvent extractive distillation process. The results indicate that the intensification process reduces the total annual cost by 3.14% and gas emissions by 29.02% compared to the basic process. This study not only provides a new idea for the design of extractive distillation process, but more importantly, it provides a reference for the screening and industrial application of mixed entrainer.