High-Temperature Interaction of Components of Spent Uranium Nuclear Fuel with Alkali Metal Carbonates in the Course of Voloxidation in the Carbex Process

摘要

Interaction of UO_2, U_3O_8, ZrO_2, Nb_2O_5, CeO_2, Ce_2O_3, Pr_6O_(11), Eu_2O_3, Yb_2O_3, Tb_7O_(12), and Re metal with lithium, sodium, and potassium carbonates in the temperature interval 300-900°C was studied using methods of thermal analysis and X-ray diffraction. The major products of the high-temperature reactions are alkali metal uranates and diuranates, and in the case of ZrO_2, Nb_2O_5, and lanthanide oxides, oxides of metals in higher oxidation states and salts of the corresponding metal-containing acids, formed by reactions of the oxides with sodium carbonate.