Epoxide-based PDMS TFC membrane fabricated via the T-FLO technique for the phenol separation

Abstract

Poly(dimethylsiloxane) (PDMS), as the valuable candidate for the phenol separation material, is modified easily owing to its various silane coupling agents and precursors. However, the reported overall mass transfer coefficient (OMTC) of PDMS is not high enough. The silane coupling agents for PDMS TFC fabrication are limited to amine-based ones. Hence, the applications of polysiloxane membranes are hindered severely. Therefore, in this work, dense PDMS films containing epoxide-based, amine-based, and epoxide-amine mixed silane coupling agents were prepared to explore their phenol mass transfer performance. And then, the effect of the precursor molecular length and the mass ratio of the precursor to the silane coupling agents were examined. Besides, the feasibility of preparing the optimized epoxide-based poly(dimethylsiloxane) (EPDMS) membranes by the thin-film liftoff (T-FLO) technique was observed. The phenol OMTC of epoxide-based PDMS TFC (TFC-E) membranes was studied for the first time. The TFC-E performed a remarkable phenol OMTC of 39.6 × 10−7 m s−1 and good long-term stability, which endowed the promising potential applications.