An anti-fouling poly(vinylidene fluoride) hybrid membrane blended with functionalized ZrO2 nanoparticles for efficient oil/water separation

Recent advances in the fabrication of organic-inorganic hybrid membranes have received a lot of attention in membrane technology for oily wastewater treatment. In this work, a hydrophilic PVDF hybrid membrane based on poly(N-acryloylmorpholine)-grafted ZrO2 nanoparticles (ZrO2-g-PACMO), was prepared via a simple phase inversion method. PACMO was firstly grafted onto the ZrO2 nanoparticles via radical polymerization, avoiding the aggregation of ZrO2-g-PACMO nanoparticles that was characterized by a sedimentation test. Then, the effects of the ZrO2-g-PACMO nanoparticles on the structures and performances of resultant hybrid membranes were systematically investigated. The cross-section and surface morphology of the hybrid membranes were observed by field emission scanning electron microscopy and atomic force microscopy. The results indicated that the higher concentration of ZrO(2)g-PACMO nanoparticles in the casting solution led to a thicker sponge-like sub-layer and a rougher surface of hybrid membranes. The prepared PVDF/ZrO2-g-PACMO hybrid membrane exhibited a lower amount of adsorbed protein than that of the pristine PVDF membrane. This behavior was revealed by pure water contact angle measurement and force-extension curves. It was also found from the oil/water filtration that the total fouling (R-t) and irreversible fouling (R-ir) were remarkably reduced, because of the higher hydrophilicity of hybrid membranes. Furthermore, the as-prepared membranes possessed also improved separation efficiency against oil/water mixtures and the rejection ratio was as high as 99.9%. Generally, a PVDF/ZrO2-g-PACMO membrane may provide potential application for efficient oil/water separation.