A method for working up of neutrons irradiated uranium

摘要

1,047,733. Separation of plutonium. UNITED STATES ATOMIC ENERGY COMMISSION. March 4, 1964 [May 10, 1963], No. 9134/64. Heading G6R. Plutonium dioxide is recovered from neutronirradiated fuel by dissolving the fuel in a fused mixture of alkali metal chlorides, sparging the solution with chlorine gas while introducing oxygen or stannic oxide as an oxidizing agent, and separating the precipitate containing PuO2. The fuel may be in the form of metal, oxide, or chloride; cladding is first removed and the fuel broken up. The preferred chloride mixture is LiCl-KCl or LiCl-NaCl. When the oxidizing agent is oxygen, a dry mixture of chlorine and oxygen is passed through the melt. When stannic oxide is used, the precipitate is treated with HC1 vapour to remove volatile tin tetrachloride. As a preliminary to the process of the invention, the solution of the fuel in the molten salt may be sparged with chlorine and then treated by the process of Specification 945,899 for the electro-deposition of UO2. The invention also includes a process of dissolving thorium and plutonium chlorides in a molten LiCl-KCl mixture, and passing an oxygenchlorine mixture through at 575‹ C. to form a ThO2-PuO2 precipitate.