Poly(trimethylsilylpropyne) Membranes for Removal of Alcohol Fermentation Products by Thermopervaporation with a Porous Condenser

Abstract

Dense membranes made of poly[1-(trimethylsilyl)-1-propyne] (PTMSP) have been studied in thermopervaporation (TPV) separation of a butanol–water binary mixture and a real acetone–butanol–ethanol (ABE) broth. When comparing PTMSP with commercially used membranes based on polydimethylsiloxane (PDMS) in the TPV process, a significant advantage of PTMSP with respect to the butanol/water selectivity is shown. The value of the separation factor for the PTMSP membrane (114) with a thickness of 61 μm is more than ninefold higher than that of the most selective Pervap 4060 commercial membrane (Sulzer Chemtech, Switzerland). The permselectivity of PTMSP membranes with respect to the butanol/water components exceeds that of commercial membranes more than fivefold. The removal of acetone, butanol, and ethanol from real fermentation broths using PTMSP membranes in the TPV process with a porous condensation surface has been studied for the first time. It has been shown that the transport and separation characteristics of PTMSP membranes in the process of separation of real fermentation broths decline with time, while demonstrating high values of the butanol/water permselectivity (4.7).