121 results about "Leaching (metallurgy)" patented technology

Leaching is a process widely used in extractive metallurgy where ore is treated with chemicals to convert the valuable metals within into soluble salts. These can then be washed out and processed to give the pure metal; the material left over is commonly referred to as tailings. Compared to pyrometallurgy leaching is easier to perform, requires less energy and is potentially much less harmful as no gaseous pollution occurs. Drawbacks of leaching include its lower efficiency and the often significant quantities of waste effluent and tailings produced, which are usually either highly acidic or alkali as well as toxic (e.g. Red mud).