Ahmed R. Bakry

 Nuclear Materials Authority, P.O.Box 530, El Maadi, Cairo, Egypt

Summary: An alternated method is carried out to acquire a selective leaching procedure for uranium from carbonate rich black shale (BS) of southwestern Sinai (0.16% U₃O₈). Uranium was present in the hexavalent state (VI) in the rock sample. This method is based on using a mixed reagent of citric acid/calcium citrate reagent in a manner to leave the carbonate, vanadium and copper almost intact for the later proceeding. The influence of different factors as concentration of citric acid/Ca-citrate, molar ratio, grain size, pH of the leach liquor solutions, S/L ratio, leaching time and temperature was investigated in order to find optimum conditions. The purpose is to formulate economic value that would realize the recovery of leaching a mixed reagent for recycling. From the obtained leach liquor, uranium can be precipitated and recovered by addition of isopropyl alcohol (IPA) to leach liquor.