Enhanced performance of thin-film nanocomposite RO/NWF membrane by adding ZnO nanospheres in aqueous phase during interfacial polymerization process

Abstract

A novel thin-film nanocomposite (TFN) reverse osmosis (RO)/non-woven fabric (NWF) membrane was prepared by adding zinc oxide (ZnO) nanospheres (30+-10 nm) during the interfacial polymerization process of m-phenylenediamine (MPD) and trimesoyl chloride (TMC) on self-made polysulfone (PSF) membrane/polyester (PET) non-woven fabric support. The improved performance of TFN RO membrane was verified in terms of water contact angle (WCA), water flux, salt rejection, antifouling properties and chlorine resistance. The results showed that the WCA value of TFN RO surface had a continuous decrease with the increasing of ZnO content in MPD aqueous solution. The water flux of composite TFN RO membranes acquired a remarkable increase with a stable high solute rejection (94.5 %) in 1 g.L-1 NaCl aqueous solution under the optimized addition amount of ZnO (1 wt%). The continuous testing of membrane separation performance after the immersion in sodium hypochlorite solution indicated that the introduction of ZnO nanospheres also dramatically enhanced the antifouling properties and the chlorine resistance of composite RO membranes.