Introducing Zirconium Organic Gels for Efficient Radioiodine Gas Removal

Iodine radioisotope, as one of the most important fission products of uranium, may cause severe damage to human health when it is accidentally discharged into the environment. Hence, efficient removal of radioactive iodine is one of the most critical issues for both used nuclear fuel (UNF) reprocessing and environmental remediation. In this work, three metal-organic gels (MOGs) were introduced for iodine removal. The presented zirconium-based MOGs, namely, CWNU, CWNU-NH, and CWNU-2NH, were prepared via moderate solvothermal reactions. These MOGs all exhibit excellent chemical stability and reusability, marked iodine sorption capability, and favorable machinability, which can even rival commercial ones. The sorption capacities are determined to be 3.36, 4.10, and 4.20 g/g, respectively. The increased amount of amino group is considered to be responsible for the elevated iodine sorption capacity and kinetics, as confirmed by combined sorption studies and XPS analysis. The presented work sheds light on the utilization of MOGs for radioiodine capture.