Nature-inspired creation of a robust free-standing electrospun nanofibrous membrane for efficient oil–water separation

Abstract

A novel flexible and free-standing electrospun Fe³⁺–PA/OTMS/PI nanofibrous membrane with superhydrophobicity and superoleophilicity was successfully fabricated by electrospinning assembly in combination with surface modification technology. The as-prepared membrane exhibited excellent resistance to high temperature, ultraviolet (UV) irradiation, corrosive liquids (such as acidic, basic, and salt solutions) and mechanical abrasion. In addition, the superhydrophobic and superoleophilic membrane could be efficiently used to separate various oil–water mixtures including dichloromethane (DCM), trichloromethane, dichloroethane, bromobenzene, and carbon tetrachloride. Furthermore, the as-prepared membrane still possesses a relatively stable and high flux level of 8424 ± 105 L m⁻² h⁻¹ after repeated used for twenty separation cycles with the separation efficiency always above 99% and the oil content in the filtrate for all the tested oil–water mixture below 5 ppm. We believe that these as-prepared nanofibers with such excellent performance, are low cost, environmentally friendly, easy to scale up and sustainable, and thereby have the potential to be used in practical applications in the treatment of industrial oily wastewater and oil–water separation.