Optimizing the Effective Parameters on Acid Leaching of Khashoomi Uranium Ore

Leaching is one the stages of hydrometallurgy which is usually applied for uranium ore processing. Uranium ores are normally leached using acidic or alkaline solutions, such as H2SO4 or Na2CO3. Khashoomi region is located in 150km southeast of Yazd city. During primarily exploration stage in Khashoomi 47 anomalies were recognized from which, anomaly 6 is the most important and promising one. In this research project the sample from Khashoomi deposit was studied using acid leaching method, to optimize significant parameters levels in process, such as size of particles, acid (H2SO4) consumption, type and consumption of oxidant, temperature, leaching time, and solid percent of pulp. Different experiments were carried out and the optimized values for above parameters were determined. It was specified that the best particle size was d80=600 microns, 80kg/t of H2SO4 consumptions, 2 hours of leaching time at 40 centigrade temperature, MnO2 type of oxidant with 5kg/t consumptions, and at equal ratio of liquid to solid (L/S). The recovery of uranium was also cross-checked, running a test using a sample with more weight, under the optimized parameters. The obtained results from this test indicated of 81% of uranium recovery which was acceptable and an indication to the previous tests results.