A facile synthesis of a highly stable superhydrophobic nanofibrous film for effective oil/water separation

An oil/water separation film with excellent durability and stable recyclability is highly desired for the treatment of oil containing effluents, like industrial oily wastewater. Herein, a novel superhydrophobic nanofibrous film (SNF) was fabricated by growing TiO2 on a collagen fiber membrane (CFM), followed by surface coating of vinyl triethoxysilane. The as-prepared SNF was well characterized by SEM, SEM-EDS and XPS. Due to the unique structure, the SNF featured superhydrophobicity with a water contact angle (WCA) of 153 degrees. When applied in the separation of oil/water mixtures, SNF exhibited a high separation efficiency of similar to 97% in 5 circles, and it showed more effective oil/water separation efficiency compared to the commercial PTFE film. SNF was also effective for the separation of gasoline/water or diesel oil/water mixtures with varied volume ratios, and all the corresponding separation efficiencies were higher than 97% even after 5 cycles. In addition, SNF could still maintain superhydrophobicity with WCA around 150 degrees after being treated by high temperature (120 degrees C), ultraviolet irradiation, water or organic solvent immersion for 24 h, manifesting an excellent durability.