Recovery of uranium from the Um Samra-Um Bakra shear zone, central Eastern Desert, Egypt

Abstract

The Um Samra-Um Bakra shear zone in the central Eastern Desert of Egypt strikes 110°, dips 45° SSW, and ranges from 30 to 500 m in width. It extends more than 10 km in length and cuts through postorogenic granites. The shear zone is dissected by three different vein types. These veins are chronologically arranged as black, red, and milky silica veins in ascending order and dissect the host rock. In this work, the uranium mineralization in the Um Samra-Um Bakra shear zone was studied with a view to recovering the uranium. The recovery of uranium from a technological sample that was found to contain 4644 ppm U was investigated by considering two possible leaching processes: agitation and pug leaching, using sulfuric acid as the leaching agent. The relevant parameters of both processes were studied. Under optimal conditions, it was possible to achieve a leaching efficiency of about 97.8% with the agitation process when NaClO3 was included as an oxidant. Leaching efficiencies exceeding 99% for U were achieved with pug leaching. A marketable product was conveniently prepared from the resulting leach liquor.