Preparation of electrically enhanced forward osmosis (FO) membrane by two-dimensional MXenes for organic fouling mitigation

Abstract

In this work, a conductive thin film composite forward osmosis (TFC-FO) membrane was firstly prepared via vacuum filtering MXenes nanolayer on the outer surface of polyethersulfone membrane followed by interfacial polymerization in the other side. Moreover, its feasibility of mitigating organic fouling under electric field was evaluated. Results indicated that the addition of MXenes greatly reduced the electric resistance of membrane from 2.1 × 1012 Ω to 46.8 Ω, enhanced the membrane porosity and promoted the membrane performance in terms of the ratio of water flux to reverse salt flux. The modified TFC-FO membrane presented the optimal performance with 0.47 g/m2 loading amount of MXenes. Organic fouling experiments using sodium alginate (SA) and bovine serum albumin (BSA) as representative demonstrated that the introduction of MXenes could effectively enhance the anti-fouling ability of TFC-FO membrane under the electric field of 2 V. The interelectron repulsion hindered organic foulants attaching into membrane surface and thus effectively alleviated the membrane fouling. More importantly, the modified TFC-FO membrane showed good stability during the fouling experiment of 10 h. In all, our work proved that introducing MXenes into the porous layer of support is feasible to alleviate organic fouling of FO membrane.