Zwitterionic functionalized chitosan with dual-antifouling for selective uranium extraction

Uranium adsorbents deployed in natural water environments rich in microorganisms for a long time are inevitably affected. Biofouling severely reduces the uranium adsorption performance and damages the structure of the adsorbents. Therefore, antifouling performance is necessary for adsorbents that extract uranium from seawater and uranium-containing groundwater. Previously reported antifouling uranium adsorbents mainly have two types: single antibacterial or anti-adhesion, and few studies have developed dual-antifouling adsorbents that combine the two antifouling pathways. In this study, a dual-antifouling adsorbent CS-MPC with both anti-adhesion and antibacterial properties was constructed. The synergistic effect of the superhydrophilic 2-methylacryloxyethyl phosphocholine (MPC) and the natural bactericidal chitosan (CS) enabled the inhibition rate of dual-antifouling CS-MPC against various bacteria to exceed 99 %. Furthermore, the uranium adsorption capacity of CS-MPC was 579 mg/g in simulated uranium-containing groundwater and 8.28 mg/g after immersion for 42 days in real seawater. The SA/CS-MPC composite beads prepared to solve powder defects also exhibited good dual-antifouling activity and uranium adsorption properties, making them potential candidates for uranium extraction. The construction of dual-antifouling adsorbents provides a new strategy for effective biofouling control.