Ammonium carbonate is not commonly used in industrial uranium leaching, although it has benefits such as selectivity, little or no attack on silicaceous materials, good opportunities for reagent recycling, and straightforward and selective recovery of uranium values. It has found application in in-situ leaching, however. When radioactive materials are handled in hot cells, it is desirable to have the simplest possible process resulting in no or minimal waste. Ammonium carbonate as lixiviant was studied for the selective recovery of uranium from a simulated residue for eventual application in the recovery of uranium from radioactive residues. The study also compared oxygen and hydrogen peroxide as oxidants. It was found that the leaching reaction is rapid at 50 °C and above, especially when hydrogen peroxide is used as lixiviant. The reagent decomposes to ammonia, carbon dioxide, and water at rather low temperatures. This can, however, be put to good effect by allowing simple recovery of the reagent, thus closing possible effluent loops and minimizing wastes, with attendant environmental benefits. The conditions for obtaining an easily filtered product were determined.
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