Preparation of sodium alginate-polyvinyl alcohol@PVDF hybrid membrane for efficient oil-water separation

Oily sewage is widespread in petrochemical and machinery manufacturing industries. Direct discharge not only wastes water and oil resources, pollutes the ecological environment, but also affects the survival and health of humans and other organisms. The traditional oil-water separation method has strong limitations, poor economy and low separation efficiency. Sodium alginate (SA) and polyvinyl alcohol (PVA) were uniformly coated on the surface of PVDF membrane, and superhydrophilic SA-PVA@PVDF hybrid membrane was prepared by multiple cyclic self-assembly. The oil-water separation experiment was carried out by using the membrane. The initial separation efficiency was 99.8%, and the overall separation efficiency remained above 98.3% after 10 cycles of regeneration experiments. This study provides a new idea for the low-cost, green and simple preparation of superhydrophilic-underwater superoleophobic separation materials.