Oil-water emulsion separation using intrinsically superoleophilic and superhydrophobic PVDF membrane

Abstract Separation of the oil-water emulsion is a complex process and recent oil-spills make it imperative to find a robust solution in order to solve adverse environmental concern. Membrane-based separation is one of the preferred choices despite the need for better membrane materials in order to have the separation process economically and operationally viable. Environmental Intrinsically superhydrophobic and superoleophilic PVDF membrane was prepared by nonsolvent induced phase inversion (NIPS) method. The newly developed membrane showed super wettability and anti-wettability, not only on the surface of the membrane film, but throughout the whole film due to the interconnected fibrous nature of the membrane. The synthesized membrane was thoroughly characterized using SEM, water contact angle and porometer and tested for the separation of water-in-oil emulsion mixtures under different operating conditions. Unlike conventional membrane, the superhydrophobic nature of the film was stable in both acidic and basic conditions. For the oil-water physical mixture, the crossflow membrane separation showed oil flux of 8800 LMH at ambient condition. For the surfactant stabilized water-in-oil emulsion, the superhydrophobic and superoleophilic membrane showed improved fouling resistance compared to the conventional PVDF membrane.