One-step facile fabrication of Mg(OH)2/PVA/ZnO membrane with superior stability and oil-water separation

The release of oily wastewater is a significant threat to both the environment and the sustainable development of society. The challenge of oil–water separation, which includes immiscible oil/water mixtures and emulsions, is exacerbated by the substantial volume of oily wastewater generated in industrial processes and daily activities. In this study, a one-step electrodeposition method was employed to fabricate a composite membrane composed of Mg(OH)2/PVA/ZnO. A uniform electric field was applied between the cathode and anode to facilitate the deposition of PVA and ZnO nanoparticles onto various metallic mesh of the cathode in the presence of Mg2+. The generation of hydrogen at the mesh surface facilitated the development of a superhydrophilic/underwater superoleophobic composite structure featuring micropores and nanosheets. The membrane durability, water flux, and separation efficiency were significantly enhanced, achieving a separation efficiency of 99.8 % and a water flux of 3.2 × 105 L·m−2·h−1. The membrane demonstrated excellent performance in separating a wide range of oil–water mixtures and emulsions, along with outstanding chemical stability and resistance to oil fouling.