Supercritical CO2 Fluid Leaching of Uranium from Sandstone Type Ores

摘要

Uranium is an important fuel for nuclear power, so the mining and milling of uranium is the base for development of nuclear power. Our experiments study is about the supercritical CO_2 fluid extraction of uranium in low grade uranium ore, and the influence of aqueous medium, oxidants, chelating agents and other factors on the uranium leaching. In aqueous media, Fe_2 (SO_4)_3 as the oxidants, supercritical CO_2 fluid extraction of uranium has the best effect, the uranium leaching rate reaches 90.44%, significantly higher than that of the conventional acid and alkaline leaching. In the process of extraction of uranium in supercritical CO_2 fluid, the uranium in uranium ore is first oxidized to hexavalent uranium, and then forms high solubility of uranyl carbonate complexes. Supercritical CO_2 fluid is expected to be used in in-situ leaching of uranium mining of the low grade sandstone uranium deposits.