Uranium extraction from seawater by novel materials: A review

There are abundant uranium resources in the ocean, from the perspective of resource utilization and ecological environmental protection, seawater uranium extraction is a way to regenerate uranium resources with high potential value. Due to the advantages of low cost, simple operation, practicality and environmental friendliness, the adsorption method has become one of the most commonly used and effective techniques for uranium extraction from seawater. This review first introduces commonly used adsorbents, mainly including carbonbased materials, metal organic frameworks (MOFs), covalent organic frameworks (COFs), biopolymers, amidoxime based materials and so on. Then, the main influencing factors of seawater uranium extraction by adsorption are listed, mainly including coexisting metal ions, salinity, pH, temperature and biofouling. Next, some experimental examples of the application of advanced techniques to speculate on reaction mechanisms such as coordination, chelation, electrostatic attraction, and adsorptive photocatalytic synergy are presented. Finally, this review puts forward the opportunities and challenges that still exist in seawater uranium extraction, and looks forward to its development prospects on this basis. The overview will help readers to further understand the key technologies of seawater uranium extraction and to discover more efficient and environmentally friendly materials for seawater uranium extraction, which is significant to support the development of nuclear power industry.