A quadruple-site, zwitterion-engineered, and antifouling fiber for efficient uranium extraction from seawater

Uranium extraction from seawater (UES) represents a crucial strategy for addressing the shortage of terrestrial uranium resources. To effectively extract uranium from seawater, the adsorbents must overcome the key drawbacks of insufficient adsorption affinity, severe salt-shrinkage effects, and significant biofouling. In this study, a highly efficient fibrous adsorbent designated PG-AO-PO 3 is developed, by integrating three strategic design elements: (1) constructing quadruple multi-site coordination, (2) in situ formation of zwitterionic units, and (3) incorporation of a highly effective antimicrobial polymer. The uranium adsorption mechanism demonstrated that the amidoxime, amide, guanidine and phosphate groups undergo multi-site coordination with uranium, so that the uranium extraction performance is significantly enhanced. The introduced PO 3 groups form zwitterionic structures through a proton transfer process, enabling the PG-AO-PO 3 fibers to exhibit excellent resistance to both salt-shrinkage effect and marine biofouling. Consequently, the uranium uptake amount of the PG-AO-PO 3 in natural seawater after 35 days was up to 8.6 mg/g. Due to its low cost, simple preparation process, high uranium capacity and excellent biofouling resistance, PG-AO-PO 3 poses a promising adsorbent for industrial-scale UES. Download: Download high-res image (278KB) Download: Download full-size image