Mechanisms of Radionuclide-Hyroxycarboxylic Acid Interactions for Decontamination of Metallic Surfaces

This project addresses key fundamental issues involved in the use of simple and safe methods for the removal of radioactive contamination from equipment and facilities using hydroxycarboxylic acids. The objectives of this research are to (i) determine the nature of the association of radionuclides with the metal surfaces commonly found at sites targeted for decontamination and decommissioning, such as plain carbon steel and stainless steel; (ii) selectively remove low levels of radionuclides such as U, Pu, Co, Cs, and Sr from contaminated metallic surfaces using hydroxycarboxylic acids (citric acid and its analogs) by elucidating the coordination, complexation, dissolution and removal mechanisms; and (iii) recover radionuclides in a concentrated form by biochemical and photochemical degradation of the extract containing radionuclide-organic complexes thereby resulting in significant reduction in secondary waste generation. The basic information derived from this study should also be applicable to decontamination of other metallic surfaces as well as porous materials such as cement