Efficient iron extraction from low grade ore using optimized HCl leaching with multi analytical characterization and kinetic investigation

The main objective of this study is to leach iron contents of a low-grade iron ore under leaching agent HCl. The effects of HCl concentration, ore quantity, leaching duration and temperature on the leaching efficiency of iron from the ore were investigated. Optimal conditions i.e. 4 g of iron ore, 3.83 M HCl concentration, 110 °C temperature, 70 min of leaching duration with constant stirring of 300 rpm, resulted in a high leaching efficiency (92%). These conditions correspond to a liquid-to-solid (L/S) ratio of 12.5 mL/g. The SEM analysis indicated that the microstructure of the ore was transformed from fine and smooth grains to large and rough grains due to leaching. The shrinking core model (SCM), to elucidate leaching mechanism, has been utilized by means of kinetic analysis. 42.16 (kilo joules per mole) of Activation energy was acquired from the Arrhenius equation. This suggests the effective extraction of Fe from the ore through HCl leaching. This leaching process can be further applied in the mining industry as an optimized process to extract iron from low grade ores. This will be more cost effective than the current processes as it will allow for material recovery from waste.