M.S. Abd El-Ghany Nuclear Materials Authority, P.O.Box 530 El-Maadi, Cario, Egypt E-mail: omneya@link.net
Summary: Yttrium group rare earths are commonly associated with uranium minerals which can be partially dissolved during the conventional sulphuric acid agitation leaching. Representative sample from Gattar (V) uraniferous material, Eastern Desert, Egypt, assayed 2475 uranium and 1070 µmL-1 of rare earths was subjected to sulfuric acid leaching for studying the ability of dissolving maximum uranium and the associated constituents of rare earths under moderate conditions taking in the consideration unaffecting the later uranium recovery processes. Acid concentration of 100 g/L without oxidant addition, 6.0 h agitation time, - 60 mesh (0.25 mm) solids grain size and leach slurry of 50% solid at 60oC were the suitable conditions and under these conditions leaching efficiency of 97.3% and 61.5% were achieved for uranium and rare earths, respectively. When these conditions were applied upon six tons on pilot scale in batches each of 250 kg, leaching efficiencies more than 96.0% for uranium and 57.0-60.5% for the rare earths was leached out. |
