Fabrication of Polytetrafluoroethylene Composite Membrane via Laser Perforating and Nanosilica Coating for Efficient Oil–Water Separation

Abstract

Oil/water separation membrane has attracted increasing attention due to the environmental issue caused by industrial oily wastewater and frequent oil spill incidents. Techniques for preparation of high-performance membranes are still in need of advancing. In this work, an environment-friendly polytetrafluoroethylene composite membrane was fabricated with a two-step method, i.e., picosecond laser perforating and subsequent nano-silica composite coating. The in-air water contact angle of the prepared membrane was 0°, and the underwater oil contact angle was over 150°, showing excellent superhydrophilic/underwater superoleophobic properties and self-cleaning performance. Results also showed that an average separation efficiency above 96% was obtained for the composite membrane for a variety of oil–water mixtures. The tailored wettability and separation efficiency remained after abrasion and corrosion tests, indicating good durability of the membrane in harsh environment.