Pervaporative separation of bioethanol using a polydimethylsiloxane/polyetherimide composite hollow-fiber membrane

Pervaporation is one of the most promising separation processes for the purification of ethanol. In this study, a composite hollow-fiber membrane with a thin polydimethylsiloxane (PDMS) active layer on a polyetherimide (PEI) macroporous support was used for pervaporative separation of ethanol produced by Saccharomyces cerevisiae from glucose fermentation broth.The pervaporation performance for ethanol/water binary mixtures was strongly dependent on the feed concentration and operating temperature for ethanol concentrations of 1–10%. The composite hollow-fiber membrane was stable over the long-term (about 160 days) with an ethanol permeation flux of 60–62 g/m2 h and a separation factor of 7–9. In comparison with published results for PDMS composite membranes, the PDMS/PEI hollow-fiber composite membrane had relatively good pervaporation performance with a total flux of 231–252 g/m2 h.

The pervaporation performance maintained in the long-term stability test of the PDMS/PEI composite hollow-fiber membrane.Figure optionsDownload as PowerPoint slideHighlights
► A composite hollow-fiber membrane was used for pervaporative separation.
► Ethanol flux and selectivity has a strong dependence on the feed concentration.
► Pervaporative ethanol separation shows good performances.
► Pervaporation membrane maintained performance in the long term test.