A review on oil/water emulsion separation membrane material

The ever-increasing oil spill accidents from industries and the daily life have caused serious economic loss, destroyed the ecological environment and threatened human health. In order to solve this problem, designing and fabricating efficient separation membrane materials is an efficient way for oil/water emulsion separation and thus has aroused tremendous attention. We present a comprehensive overview on the separation membrane materials with controlled pore structure, tunable wettability for highly efficient oil/water emulsion separation. Separation mechanism was introduced at first, followed by introduction of the most frequently studied membrane materials. Based on the membrane substrate, general oil/water emulsion separation membrane can be categorized into polymer membrane, inorganic membrane, metal mesh membrane, gel membrane and biomass membrane. Besides, faced with the common problem of membrane pollution and damage, special functional membranes such as self-cleaning membrane, self-healing membrane, Janus membrane, and smart responsive membrane have aroused wide attention in recent years. For each membrane material, representative studies have been summarized, focusing on the synergy influence of the porous structure and selective wettability on the oil/water emulsion separation performance. Finally, the challenges, current trends and future perspectives of the oil/water emulsion separation membrane materials have also been proposed.