Pervaporation performance of PTMSP membranes at high temperatures

Abstract

The separation of ethanol–water mixtures by pervaporation has been carried out through poly(1-trimethylsilyl-1-propyne) (PTMSP) membranes. This polymer is known to be alcohol-selective and shows high selectivity and ethanol permeation rate. The performance of this polymer was studied at high temperatures over long periods of time to examine deterioration of its transport properties. The PTMSP membrane shows an initial separation factor (α) of about 10.7 and specific permeation rate (R) of 0.054 g m m−2 h−1 for a 10 wt % ethanol solution. Although this polymer has good characteristics for the separation of gases and liquid mixtures, its selectivity decreases with operating time, reaching a value of 8 after 450 h. On the other hand, the specific permeation rate remains almost constant except during the swelling period, in which it decreases to a value of 0.035 g m m−2 h−1. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2255–2259, 2003