Pervaporative removal of acetone, butanol and ethanol from binary and multicomponent aqueous mixtures

Results of research on the effectiveness of selected hydrophobic PDMS-based membranes in the pervaporative removal of acetone, butanol and ethanol from binary and quaternary aqueous mixtures are presented. Various investigated PDMS membranes exhibit high selectivity towards butanol. Values of separation factor beta in contact with 1 wt.% BuOH are in the range from 27 (Pervatech PDMS 2.0) to 40 (Pervap 1070 PDMS 0.2). Pervatech PDMS 2.0 membrane, showing the highest PSI value, was chosen for experiments with binary and quaternary aqueous mixtures. Simulation of batch pervaporation process showed that during 300 min of the process it is possible to remove over 95% of organics from the feed mixture, containing initially 3 wt.% of ABE mixture and with feed to membrane area ratio of 100 kg m(-2). It was also found that a longer batch pervaporation process results in a more diluted permeate. Such phenomenon is caused by the fact that organic fluxes decrease with time whereas water flux is constant during batch process. (C) 2014 Elsevier B.V. All rights reserved.