UNIT PROCESSES IN HYDROMETALLURGY: LEACHING, PURIFICATION OF LEACH LIQUOR

Hydrometallurgy is an important technique within extractive metallurgy that enables the recovery of metals from ores through aqueous solutions. This paper aims to provide a comprehensive overview of unit processes involved in hydrometallurgy, particularly focusing on leaching and purification of leach liquor. A systematic methodology is presented that includes four key steps: leaching, separation of leach liquor, recovery of metal from the leach liquor, and reagent recovery. The leaching process selectively dissolves desired elements using specific solvents and may require preliminary preparation operations such as grinding and roasting. Following this, the leach liquor is separated from solid residues using various material separation techniques. The recovered metal is processed further using diverse methods including evaporation and ion exchange. Additionally, the study highlights the advantages of hydrometallurgy over traditional pyrometallurgical methods, particularly its suitability for processing complex ores, environmental benefits, and ability to recover valuable by-products. This analysis underscores the significance of hydrometallurgy as a sustainable approach in the field of metallurgy, especially amidst increasing concerns over environmental pollution and resource depletion.