Bio leaching of Uranium - bearing material from Abu Thor area, West Central Sinai, Egypt for recovering uranium

A uranium-bearing material was recorded within the Intra-Carboniferous Paleokarst Profile of Um-Bogma Formation at Abu Thor area, West Central Sinai, Egypt. The present paper is concerned with the bio leaching of U and Cu using Aspergillus Niger (A. Niger) followed their proper recovery. The working Abu Thor representative sample assays 0.22% U as the element of interest as well as up to 25% CuO beside the other rock constituents SiO2 (33%), Al2O3 (10.4%) and CaO(8.5%). The effective bio leaching of U and Cu from Abu Thor ore sample using A.Niger was performed at the following optimum conditions: an incubation time of 6 days, sample/ liquid (S/L) ratio of 1/10, ph value of 1 and a temperature of 60 degree C. The prepared bio leach liquor assays 0.19 g/l of U and 15.8 g/l of Cu with leaching efficiencies of 97% and 79%, respectively. Uranium was recovered using 25% TBP in kerosene at O/A ratio of 1/1 and contact time of 5 min with achieved extraction efficiency of 96%. However the stripping of U was conducted by using 8% Na2CO3 at A/O ratio of 1/1 and contact time of 5 min with stripping efficiency reached 99%. On the other hand, Cu was directly precipitated as CuS using the freshly released H2S gas with the addition of solid Na2S. The optimum precipitation conditions were S/L ratio of 1/100, ph 1.5 and room temperature where the precipitation efficiency of Cu achieved 99%