Smelting

Chemical reduction or smelting is a form of extractive metallurgy. The main use of smelting is to produce iron and steel from iron ore. Smelting is also used to extract copper and other base metals from their raw ores.

It makes use of a chemical reducing agent such as carbon (coke, or in earlier times charcoal) to change the oxidation state of the metal ore. When coke is mixed with iron ore and heated, the oxygen will move from the iron to the carbon. The iron will be reduced, and the carbon will be oxidised, producing carbon dioxide and carbon monoxide. A fluxing agent such as limestone is used to remove the accompanying rock gangue as slag (also called scoria or cinder).

See also

• Blast furnace
• Furnace
• Metallurgy
• Pyrometallurgy