Extraction of uranium from seawater by hydrophilic dihydroxamic acid type polymers

The adsorptivity of chelating resins for uranium is affected not only by the nature of the ligands but also by the chemical properties of the polymer support. In this work, the following new crosslinking agents were synthesized: triethyleneglycol bis (vinylbenzyl) ether (EGV) and hydroquinone bis (vinylbenzyl) ether (HQV). Dihydroxamic acid polymers crosslinked by divinylbenzene, EGV or HQV adsorbed only 0.1 to 5 μg/g of uranium from seawater in 6 days. By introduction of N, N-dimethylacrylamide into the dihydroxamic acid polymer, the rate of adsorption for uranium from seawater increased significantly. For the microporous gel type polymers, hydrophilic property of the gel phase was found to increase the rate of adsorption for uranium. Uranium uptake reached 70 μg/g in 7 days. (author)