DISSOLUTION OF URANINITE IN ACID-SOLUTIONS

The purpose of this work was to assess the oxidative dissolution of ur anium from a uraninite-containing rock in acid sulfate solutions under test conditions relevant to uranium leach mines and acid mine waters. Uranium dissolution in acidified mineral salts solution was slow and the predominant carbonate mineral (rhodochrosite) in the rock sample c ontinued to consume acid. Bacterial inoculation (Thiobacillus ferrooxi dans) and additional Fe2+ or S-0 were tested in efforts to enhance the dissolution. Addition of Fe enhanced the solubilization of uranium, w hereas S-addition had little incremental effect on the dissolution wit h and without bacterial inoculation. (C) 1998 Society of Chemical Indu stry.