Alkaline leaching for recovery of uranium and copper from calcareous shale, um bogma formation, G. Allouga Southwestern Sinai, Egypt

Abstract EN

Calcareous shale samples, from Um Bogma Formation, at Gabel Allouga, south western Sinai, Egypt, assaying 874 ppm U and 2050 ppm Cu have been investigated for the recovery of uranium and copper.

Different factors affecting alkaline leaching of uranium and copper from the calcareous shale under study were investigated.

It was found that a solution containing a mixture of 2.0 M ammonium carbonate and 0.5 M ammonium bicarbonate, at a solid sample to liquid ratio (S/L) of 1.0/4.0 and stirred for 3.0 hours at 60oC using H2O2 as oxidant attains the highest leaching efficiency.

The leaching efficiency was found to be 91.5% and 94.7% for U and Cu elements, respectively.

Recovery of uranium and copper was first achieved from the leach liquor using lewtit mono plus M 500 anion exchange resin, for separation of uranium.

This was followed by washing and uranium stripping by NaCl solution.

Uranium was then precipitated as sodium diuranite using sodium hydroxide.

From the leach liquor free from uranium, copper was precipitated by evaporation followed by calcination at 650oC.

The purity of the products was checked by XRF technique.