Comprehensive biocompatible hemp fibers improved by phosphate zwitterion with high U(VI) affinity in the marine conditions

The accelerated consumption of land-based uranium (VI) (U(VI)) ores is gradually transformed into seawater U (VI) recovery and extraction to meet the needs of energy strategy and environmental safety. However, the extreme low concentration, multiple co-existing ions with high concentration and numerous marine biofoulings pose challenges to the adsorbents utilized in marine. Considering the compatibility with biological marine systems, the natural abundant, economical and eco-friendly hemp fibers (HFs) were functionalized by 2-hydroxyethyl acrylate (HEA) induced side-chains, which supports future modification with Vinylphosphonic acid (VPA) and 2-(methacryloyloxy)ethyl 2-(trimethylammonio)ethyl phosphate (MPC). The optimized product named as HFHPC exhibits an outstanding distribution coefficient of 1.44 +/- 0.19 x 10(4) mL.g(-1) for U(VI) in a 100 times concentration of co-existing ion solution than those in seawater, an ultra-fast total infiltration time of 0.2 s and a hydration layer induced antifouling property. After immersed in marine for 35 days (Yellow Sea, China), the adsorption capacity of HFHPC is 432.49 +/- 7.90 mu g.g(-1) (a high U/V mass ratio of 8.3), which is 3.5 times higher than that of HFP (only prepared by VPA). This phosphate zwitterion promoted biocompatible HF-based material will be an alternative adsorbent for seawater U(VI) extraction with great affinity and antifouling property.