Triple antifouling strategies for reverse osmosis membrane biofouling control

Abstract

Triple antifouling strategies with fouling release, fouling resistance and contact killing attributes have been utilized for the control of reverse osmosis membrane biofouling. The membrane surface modification procedure is simple and time-efficient. After the interfacial polymerization process, the membrane was rinsed by n-hexane with addition of 2,2,3,4,4,4-hexauorobutyl methacrylate (HFBM), then exposed to UV irradiation for 20s, and finally immersed into a tobramycin (TOB) aqueous solution for 30s. The resultant membrane maintains the high permselectivity of the virgin membrane. Because of the synergistic effects of low-surface-energy brushes (fouling release) and hydrophilic TOB segments (fouling resistance) on the modified membrane surface, the membrane demonstrates superior antifouling property. Further, owing to the bactericidal attribute of TOB, the membrane exhibits strong antimicrobial activity. The membrane shows high antibiofouling property due to the triple antifouling strategies. The fouling results of combined foulants also highlight the membrane antifouling and antibiofouling properties. Moreover, the membrane shows excellent performance stability during the long-term cross-flow test and chemical cleaning process.