Efficient removal of dyes and antibiotics from oily wastewater by polypropylene/ZIF-67 composite membranes with underwater superoleophobicity and persulfate advanced oxidation processes

Porous membranes have been fabricated and modified for the separation and purification of wastewater. Although they always suffer from fouling caused by various materials such as oils, dyes, and antibiotics. It is difficult to deal with the boring membrane fouling by one antifouling strategy including hydrophilicity/underwater superoleophobicity. In this work, a synergistic antifouling mechanism combining low oil adhesive underwater superoleophobicity and excellent persulfate advanced oxidation processes (PS-AOPs) performances was developed by facilely loading ZIF-67 catalysts on polypropylene (PP) membranes. The as-prepared composite membranes have stable underwater superoleophobicity and low oil adhesion, which can efficiently separate oil from oil-in-water emulsion and prevent oil adhesion. Moreover, the ZIF-67 catalysts on the composite membranes have excellent degradation performances against various foulants such as methylene blue (MB), tetracycline (TC), and levofloxacin (LVFX), which endow the composite membrane with enhanced antifouling properties during the separation of an oil-in-water emulsion containing MB, TC, and LVFX. The synergistic antifouling mechanism of low oil adhesive underwater superoleophobicity and advanced PS-AOPs provides a facile and efficient strategy for improving the antifouling of the porous membranes in real wastewater purification.