A conductive PVDF-Ni membrane with superior rejection, permeance and antifouling ability via electric assisted in-situ aeration for dye separation

Abstract

Ultrafiltration (UF) membrane has recently drawn interest in textile and dyeing wastewater treatment due to its unique advantages of low-cost and large flux. However, its low rejection to dyes and developing appropriate membrane materials remain the major hurdles for its large-scale application. Herein, we developed a novel conductive polyvinylidene fluoride (PVDF)-Ni membrane combined with an external electric field to treat typical dyes. The membrane could be fabricated by a facile and low-cost method. The conductive PVDF-Ni membrane showed favorable rejection rate of Congo red (CR) (100%) and extremely high permeance (137.5 ± 6.8 L m−2 h−1 bar−1). To our knowledge, the permeance has exceeded the maximal literature record for the membranes with similar rejection rates of CR. The novel membrane combined with external electric field also provided a unique aeration mode: in-situ aeration, due to its good electrocatalytic activity for hydrogen evolution reaction (HER) (overpotential of 157 mV at the current density of 10 mA cm−2). Benefit from the in-situ aeration, the PVDF-Ni membrane showed 94% flux recovery after filtration of bovine serum albumin (BSA). Additionally, the PVDF-Ni membrane exhibited evident resistance to dye absorption and antibacterial activity. These versatile proprieties, together with the facile fabrication process, indicated the tremendous application prospect of the fabricated PVDF-Ni membrane for textile and dyeing wastewater treatment.