▎ 摘　　要

There are positively charged Ca2+ and Mg2+, negatively charged colloids and lots of bacteria in seawater. The different surface potentials of ultrafiltration membranes may lead to different adsorption properties for con-taminants in seawater when ultrafiltration membranes were applied to the pretreatment of Reverse Osmosis process. Herein, this work prepared modified ultrafiltration membranes with different surface potentials using three GO-based materials, and investigated the anti-fouling of Ca2+, Mg2+, humic acid, the anti-bacterial adhesion performance and mechanisms of modified ultrafiltration membranes under simulated seawater con-ditions. Results showed that the modified membranes exhibited enhanced hydrophilicity, anti-fouling perfor-mance, antibacterial property and permeability compared with the unmodified polyvinylidene fluoride membrane. Conspicuously, with the highest surface potential among all membranes, quaternized graphene oxide modified ultrafiltration membrane (QGO-M) presented the best anti-fouling property to Ca2+, Mg2+, humic acid and antibacterial property. In particular, the flux recovery rate against the simulated seawater solution con-taining humic acid and the surface bacteriostatic rate against salt-tolerant bacteria of QGO-M were 95.7% and 97.9%, respectively. The results can provide an important reference for the investigation of modified ultrafil-tration membranes suitable for seawater filtration.