Biofouling increases operational costs and downtime, significantly reducing membrane life and posing a persistent challenge for membrane installations. This work demonstrates a hierarchically designed electroconductive membrane for in situ electrochemical cleaning of biofouling. This composite membrane, made from a poly(vinylidene fluoride) polymer via the nonsolvent-induced phase separation (NIPS) method, reduces biomass adhesion by 85% and promotes effective regeneration via electricity-driven cleaning. Incorporation of laser-induced graphene (LIG) into the polymer matrix provides sufficient surface roughness to inhibit biofilm formation and induce electrochemical activity. The membrane, while maintaining a high rejection of up to 95% for PEG 400, achieved a high pure water permeability of ∼400 LMH bar-1 with a molecular weight cut-off of ∼450 kDa. Various characterization techniques, including SEM, FTIR, Raman spectroscopy, and XPS, confirmed the formation of ultrafiltration membranes. Applying a 3 V cathodic potential during cross-flow regeneration achieved a flux recovery of ∼100%, outperforming cross-flow cleaning under identical conditions. The fabricated composite membranes also demonstrated mechanical stability, breaking at a stress of 26.23 MPa and a total membrane resistance of ∼9.6 × 1012 (m-1). The present study illustrates advancements in electricity-assisted self-cleaning membranes and their enhanced suitability in various treatment environments. These membranes will address the critical need for efficient water treatment solutions, reducing energy and chemical use while minimizing downtime.
Misra et al. (Mon,) studied this question.