Fundamental study for decorporation of plutonium by chelating agents. Coordination analyses of simulated plutonium with chelating agents by X-ray absorption spectroscopy

Internal contamination of plutonium in nuclear accidents is of critical concern. In the present study, chemical forms of zirconium (Zr), a simulated plutonium, coordinated with the organic/inorganic ligands as well as decorporation chelating agents were estimated based on X-ray absorption spectroscopy. Chelating agents used were 1-hydroxyethane-1, 1-diphosphonic acid (EHBP) and diethylenetriaminepentaacetic acid (DTPA). First coordination sphere of the Zr-EHBP complex, which was octahedral structure, was significantly different from other ligands such as carbonate, phosphate and DTPA. Furthermore, it was found that the Zr-EHBP complex was more stable than Zr-DTPA complex. These findings would be useful for the effective excretion of internal contamination of plutonium. (author)