Hydrometallurgy is a method for obtaining metals from their ores, concentrates, and recycled or residual materials by preparing an aqueous solution of a salt of the metal and recovering the metal from the solution. This process is used in extraction of less electro positive or less reactive metals like gold and silver. Hydrometallurgy process typically consists of the following three stages:
- Solution concentration and purification
- Metal or metal compound recovery
The operations usually involved are leaching, or dissolution of the metal or metal compound in water, commonly with additional agents; separation of the waste and purification of the leach solution; and the precipitation of the metal or one of its pure compounds from the leach solution by chemical or electrolytic means. Dilute sulfuric acid is the most common leaching agent used in the process. Edelweiss Applied Science and Technology journal is an open access maintaining high standard quality articles of hydrometallurgy.