Fabrication of novel mixed-matrix membrane and its pervaporation process integration with distillation for energy-saving separation of DMC/methanol azeotropic mixture

Abstract

Separation of azeotropic mixtures is a typical energy-intensive process in chemical industry, in which pervaporation membrane process shows great potential in energy efficiency. However, the performance of commercial membranes such as polydimethylsiloxane (PDMS) is unattractive for practical application. Henein, for the first time, we employed microporous MAF-6 as a new filler incorporating into PDMS membrane for pervaporation separation of DMC/methanol azeotropic mixture. The resulting MAF-6/PDMS mixed-matrix membrane with the optimal filler size of 300 nm and filler loading of 12 wt% exhibited highly DMC permeability (651–811.5 Barrer) and selectivity (10.1–10.4) during 31 days continuous separation process, which fairly exceeds the state-of-the-arts membrane performance. A pervaporation-distillation coupled process was further proposed for the purification of DMC/methanol mixtures, showing 55.7 % of energy-saving compared with conventional distillation process.