Improvement in fouling resistance of silver-graphene oxide coated polyvinylidene fluoride membrane prepared by pressurized filtration

Abstract

Abstract Polyvinylidene fluoride (PVDF) membranes are widely used in microfiltration and ultrafiltration because of their high chemical resistance, thermal stability, and mechanical strength. However, the hydrophobicity and high roughness of the PVDF membrane surface make it vulnerable to membrane fouling. Therefore, engineered nanomaterials such as graphene oxide (GO) have been coated to the membranes to improve its fouling resistance. In this study, PVDF membranes were coated with different concentrations of silver functionalized graphene oxide (Ag-GO) nanocomposite suspensions (0.01–0.3 mg ml−1) via pressurized filtration process. The fouling resistance of Ag-GO coated PVDF membranes was significantly enhanced due to increased hydrophilicity and smoother membrane surface. The initial feed water flux of modified membranes increased up to 53% when compared to that of the pristine PVDF membrane. Also, the flux recovery rate and antibacterial properties of Ag-GO/PVDF membranes were higher than that of the pristine membrane. Ag-GO was stably coated on the membrane surface and the enhanced performance resulting from modification with Ag-GO was maintained after the membrane backwash. We expect that our results could contribute to the development of highly reusable antifouling membranes coated with inorganic nanocomposites.