Hydrometallurgy is a branch of metallurgy that involves the extraction of metals from their ores using aqueous solutions. This process typically includes leaching, where chemicals dissolve the desired metal, followed by separation and purification techniques to recover the metal in a usable form. It is often used for metals like gold, copper, and nickel. This method is favored for its lower environmental impact compared to traditional pyrometallurgical processes, which involve high temperatures and can produce harmful emissions. Hydrometallurgy is also more efficient for certain ores, making it a valuable technique in the mining and recycling industries.