Pervaporation Performance of Polydimethylsiloxane-Polyvinylidene Fluoride Composite Membrane for Butanol Recovery from Model Solutions and Acetone-Butanol-Ethanol Fermentation Broth

Abstract

Pervaporation has been identified as the most promising separation technology for butanol recovery in acetone-butanol-ethanol (ABE) fermentation, to overcome two main obstacles, low yield and high separation cost in the industrial-scale butanol production. In this work, we investigated the pervaporation performance of a thin flat polydimethylsiloxane (PDMS)-polyvinylidene fluoride (PVDF) composite membrane for butanol recovery from model solutions and ABE fermentation broth. The PDMS-PVDF composite membrane exhibited a high total flux of 1330 g m–2 h–1, and relatively higher separation factors of 21.2, 17.2, and 4.5 for acetone, butanol, and ethanol, respectively, with ABE-water solution. Compared to ABE-water solution, the total flux decreased by 3.25% and separation factors increased by 1.40%, 3.21%, and 3.92% for acetone, butanol, and ethanol in ABE fermentation broth, indicating that the negative effect of impermeable components present in the ABE fermentation broth was negligible. The excellent pervaporation performance and long-term operational stability of PDMS-PVDF composite membrane can enhance the efficacy of butanol recovery, thus it has potential to be used as a competitive pervaporation membrane in ABE fermentation process.