Preparation of amidoxime modified porous organic polymer flowers for selective uranium recovery from seawater

Abstract

• POP-F structure was developed by free radical polymerization method. • Amidoxime modified POP-F material showed selective U(VI) adsorption. • POP-AOF shows fast and efficient U(VI) adsorption from natural seawater. • The adsorption capacity of POP-F and POP-AOF are 149.1 ± 0.2 and 500.1 ± 0.5 mg/g. Simple and facile technologies for efficient uranium(VI) removal from seawater is highly interesting for energy and environmental sustainability. By take advantage of the polymerization of acrylonitrile, amidoxime modified porous organic polymer flower-like structure (POP-AOF) adsorbent is synthesized. POP-AOF is of great interest for energy and environmental applications, since their unique structures not only provides high functionality but also accelerates high selectivity via secondary building units. The unique structure of POP-AOF showed multistep kinetics controlled by chemisorption and intraparticle diffusion model. In practical applications, POP-AOF performed as an efficient adsorbent for selective uranium(VI) removal from simulated solution and seawater are investigated. Time-dependent measurement of uranium(VI) adsorption capacity and half-saturation time of seawater exposed POP-AOF is analyzed using a one-site ligand saturation model. The coordination was analyzed by spectroscopic analysis and amidoxime groups of POP-AOF act as a bidentate ligand to trap uranium(VI) from seawater. This work addresses the potential of acrylonitrile and amidoxime chemistry for the development of new adsorbents for efficient uranium(VI) removal from seawater.