The Effect of Acid Concentration on the Chemical Leaching of El-Gedida High-Ba Iron Ore, El-Bahariya Oasis, Western Desert, Egypt

Abstract

El-Gedida high-Ba iron ore was subjected to microscopic, mineralogical and chemical characterizations followed by chemical leaching using HCl. The microscopic investigations revealed that the textural relationships between barite and iron minerals are complicated, resulting in a difficult liberation during the comminution process. XRD analysis of the studied ore indicated the presence of hematite and goethite as the dominant iron minerals and barite, quartz and halite as gangue minerals. Chemical assays using XRF showed that the investigated ore contains 42.29% Fe2O3 (29.58% Fe total), 36.99% BaO and 16.95% SO3. The pre-treatment operations involved crushing and milling up to -150μm particle size. The processing operation included chemical leaching of 15 gm representative sample of the ground ore using acidic medium of HCl at fixed agitation speed 900 r/m. The leaching was followed by filtration, solvent extraction and precipitation processes. The resultant dual concentrate is divided into iron fraction containing 66.11% Fe with 99.84% iron recovery and barite concentrate containing 66.85% BaO (99.81% recovery) and 30.53% SO3 (99.47% recovery). The resultant iron fraction is accepted as a blast furnace feed charge for the Egyptian Iron & Steel Company, while barite fraction can be used for the oil industry and glassmaking.