The nuclear disasters of Chernobyl and Fukushima presented an urgent need for finding solutions to treatment of radioactive wastes. Among the by-products of nuclear fission is radioactive 137 Cs, which evokes an environmental hazard due to its long half-life (>30 years) and high solubility in water. In this work, a water-soluble organic ligand, readily obtained from alloxan and 1,3,5-benzenetriol, has been found to selectively bind and precipitate Cs+ ions from aqueous solutions. The special rigid structure of the ligand, which consists of a "tripodal" carbonyl base above and below an aromatic plane, contributes to the size-driven selectivity towards the large Cs+ ions and the formation of a giant, insoluble supramolecular complex. In addition to the low costs of the ligand, high yields and effectiveness in precipitating Cs+ ions, the Cs-complex revealed a high endurance to continuous doses of γ-radiation, increasing its potential to act as a precipitating agent for 137 Cs.
Keywords: alloxan; nuclear waste; radioactive cesium; supramolecular chemistry; tripodal ligands.
© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.