A novel amidoxime-functionalized covalent organic framework for removal of U(VI) from uranium-containing wastewater with appreciable efficiency and selectivity

This work fabricated a novel two-dimensional (2D) amidoxime-functionalized covalent organic framework (COF) (named HDU-102-AO) for U(VI) extraction. It had a spiny rod structure, high crystallinity, appreciable specific surface area, excellent pore size structure and exceptional stability. Batch experiments demonstrated HDU-102-AO had an impressive capacity for adsorbing uranyl ions, up to 389.08 mg g −1 . It maintained a high adsorption ability at a wide pH range, with an ultra-high selectivity toward interfering ions. In summary, HDU-102-AO with excellent stability and adsorption performance, provided a practicable way for COF preparation, and could be served as a potential adsorbent for uranium adsorption.