Alkaline ion exchange fibers constructed by UV-induced radical polymerization for efficient uranium recovery from wastewater and seawater

Extracting uranium from natural seawater and wastewater is an effective approach to alleviating the current energy crisis and promoting green development in the nuclear industry. Herein, novel collagen fibers (CFs)-based strong alkaline ion-exchange fibers (CFs-SAA-IEF) were prepared through free radical polymerization initiated by ultraviolet light irradiation and an amination reaction. The CFs-SAA-IEF fibers exhibited an impressive adsorption capacity of 675.68 mg g⁻¹ at pH = 8, along with exceptional selectivity, achieving a K_d value of 1.24 × 10⁴ mL g⁻¹. Notably, due to the ion-exchange effect, CFs-SAA-IEF showed rapid adsorption kinetics, achieving a uranium removal rate of 85.9 % within 120 min. Meanwhile, the incorporation of quaternary ammonium groups imparted the adsorbents with excellent antibacterial properties even in complex aqueous environments. In addition, CFs-SAA-IEF demonstrated an exceptional adsorption performance and a high removal rate of uranium in wastewater and seawater by fixed-bed column adsorption system. Based on the XPS spectra and DFT calculation, uranyl ions are captured by the adsorbents through chemisorption, involving the ion exchange of chloride ions with uranyl ion complexes. In summary, the CFs-SAA-IEF fibers are promising candidates for the efficient recovery of uranium from seawater and wastewater.