Physicochemical principles of preparation of U(VI) carbonate solutions for extraction reprocessing in the Carbex process

Abstract

Physicochemical principles of preparation of U(VI) carbonate solutions in the step of oxidative dissolution of U₃O₈ and UO₂ in the Carbex process are considered. Carbonate solutions with the U(VI) concentration higher than 100 g L^–1, suitable for subsequent final purification of uranium by extraction, can be prepared under the conditions of formation of U(VI) carbonate–peroxide complexes in the course of dissolution with prevention of hydrolysis of U(VI) compounds. The behavior of impurities simulating some fission products in the course of oxidative dissolution was studied, and the decontamination factors of U(VI) from the chosen simulated fission products were determined.