Low-pressure driving Co3O4/PAN nanofiber membrane with peroxymonosulfate activation self-cleaning for efficient wastewater purification

Nanofiber membrane separation technologies are promising for separation of emulsions, but it is still limited by membrane fouling. Herein, a new low-pressure driving Co3O4/polyacrylonitrile (PAN) nanofiber membrane (CPNFM) with peroxymonosulfate (PMS) activation self-cleaning ability was developed by simple electrospinning technology. The effects of Co3O4 dosage on the properties and structures of resulting nanofiber membranes were investigated. The results revealed excellent superhydrophilic/underwater superoleophobic properties of the optimized CPNFM even under harsh conditions, such as acid, alkali and salt. Under sole gravity-driven, the optimized CPNFM efficiently separated multiple surfactant-stabilized emulsions with high separation efficiency (>99%) and superior flux (>300 L m−2 h−1). The optimized CPNFM also displayed a good catalytic effect toward the degradation of organic dyes through PMS activation. The effective synergy of the optimized CPNFM can also efficiently separate mixed wastewater composed of emulsion and organic dyes with high efficiency (99% for emulsion and 98% for methylene blue) and superior flux (>300 L m−2 h−1). Additionally, CPNFM displayed excellent self-cleaning ability, with restored separation performance after cycling through simple PMS activation. Overall, the high separation efficiency, good stability, and self-cleaning capability of the proposed CPNFM make it a potential candidate for long-term wastewater purification.