A novel in-situ micro-aeration functional membrane with excellent decoloration efficiency and antifouling performance

While membrane technology emerges as one of the promising candidates for printing and dyeing wastewater treatment, it still suffers problems of trade-off effect and membrane fouling. It is therefore highly desired to fabricate high-performance membranes. This study reported a new functional polyvinylidene fluoride (PVDF)-Ni-Co membrane fabricated via an in-situ reduction method. The PVDF-Ni-Co membrane displayed conductive property, magnetic property and special in-situ micro-aeration function under assistance of electric field. Benefiting from in-situ micro-aeration function, the membrane showed excellent decoloration efficiency to Rhodamine B (RB), Congo red (CR) and methylene blue (MB) solutions. Particularly, the PVDF-Ni-Co membrane possessed 98.33% rejection to CR solution with flux up to 69.30 L m(-2) h(-1).bar(-1), which is far better than the data reported in the literature. Moreover, in-situ micro-aeration was confirmed to be critical to enhance membrane antifouling performance. Cycling filtration results revealed that flux recovery rate (FRR) of PVDF-Ni-Co membrane reached to 90% and 94% for sodium alginate (SA) and bovine serum albumin (BSA) solutions, respectively. Thermodynamic calculation suggested that attractive energy of interaction between PVDF-Ni-Co membrane and foulants was largely reduced so that the foulants could hardly adhere onto membrane surface. This study simultaneously provided interesting findings regarding functional PVDF-Ni-Co membrane as well as its fabrication strategy, and new membrane fouling mitigation method of in-situ micro-aeration.

Automated summary

In this study, a PVDF-Ni-Co membrane was fabricated using an in-situ reduction method, showing excellent conductivity, magnetism, and in-situ micro-aeration function. The membrane exhibited outstanding decoloration efficiency to RB, CR, and MB solutions, with a rejection rate of 98.33% to CR solution. Additionally, in-situ micro-aeration was confirmed to be critical in enhancing membrane antifouling performance.