High flux, self-cleaning electrospun nanofiber membrane using one-step blending method for highly efficient oil-in-water emulsion separation

Membrane separation technology is a vital method for separating oil/water emulsions. However, membrane fouling caused by repeated use has brought a series of problems such as reduced permeation flux and poor recycling. Herein, we fabricated a high-flux and self-cleaning electrospinning nanofiber membrane Polyacrylonitrile-NH2-MIL-88B(PAN-NH2-M88B) by a facile one-step electrospinning blending method for highly efficient oil/water emulsion separation. Benefit from the constructed micro/nano rough structure and hydrophilic surface of NH2-MIL-88B(NH2-M88B), the PAN-NH2-M88B membrane exhibited excellent separation performances, high wettability and permeation flux after multiple oil/water emulsion separation tests under visible light irradiation. The fabricated nanofiber membrane can achieve a high separation efficiency of 99.5 % and a high flux of 5095–7662 L m−2h−1 respectively for five types of oil-in-water emulsions. More importantly, the flux of the fabricated nanofiber membrane is 2–3 times that of the membrane prepared by the traditional phase conversion method, which greatly reduces the separation time and improves the separation efficiency. Moreover, the flux of the oil-contaminated membrane can be restored by simple visible light irradiation, demonstrating excellent photocatalytic self-cleaning property. Therefore, the membrane has good stability and can be reused for many times with little change in separation efficiency and flux. Owing to the facile preparation method and the excellent performances, the developed nanofiber membrane was expected to be an ideal candidate for industrial oil–water emulsion separation.