Preparation of functionalized polyethyleneimine materials and studies on its uranium adsorption properties

Extracting uranium from water is of great significance for environmental protection and nuclear energy development. Herein, the Amidoximation Polyethylenimine-Monomer (PEI-MO-AO) with a porous block was synthesized. The adsorbent was formed by crosslinking polyethyleneimine and the polymers of terephthalaldehyde and diaminomaleonitrile and the following amidoximation enhanced the adsorption performance. Accordingly, the porous structure endows the PEI-MO-AO a good hydrophilicity. The adsorption results exhibited that the maximum capacity reached 218 mg·g^-1 at a pH of 6 and can adsorb uranium over a larger pH range. Besides, it maintained a distribution coefficient of 8760 mL·g^-1 for uranium despite the high-intensity interference of other ions. After six consecutive adsorption cycles, the removal rate of uranium ions sustained at 81.6%, and the uranium adsorption capacity maintained a relatively elevated value of 189.31 mg·g^-1. The PEI-MO-AO porous network polymeric material exhibited significant potential as an adsorbent, offering novel insights into the domain of uranium extraction and removal.