Abstract
In pursuance of addressing the global water shortage problem, this work was designed to fabricate carbon materials-based forward osmosis thin-film composite (FO-TFC) membranes with high flux and high salt rejection properties. In this study, a novel method has been developed which was conducted by coating the surface of a reduced graphene oxide (rGO) modified poly(ethylene terephthalate) (PET) nonwoven fabric with polydopamine/graphene oxide (PDA/GO) prior to the interfacial polymerization of trimesoyl chloride (TMC) and m-phenylenediamine (MPD). Results showed that coating of the PDA/GO layer on the front-side of PET nonwoven substrate facilitated the formation of a denser selective polyamide（PA）layer during interfacial polymerization process to reduce reverse salt flux; the PDA/GO layer on the back-side of PET nonwoven endowed the substrate with catechol and ethylamino groups to enhance the hydrophilicity, which result in an increase in water flux. The TFC membranes fabricated by coating rGO on Ahlstrom 3324 PET nonwoven surfaces followed by coating of PDA/GO (with 80 μg/ml GO) and interfacial polymerization of PA showed a highest water flux of 3.64 LMH and the Ahlstrom 3254 PET nonwoven with same procedure demonstrated a lowest reverse salt flux 0.77 gMH in static FO test using deionized water as the feed along with 1 M NaCl draw solution in the FO mode. It showed that the feasibility of this novel method to fabricate FO-TFC membrane with good properties.