smelting reduction

Reduction smelting is a pyrometallurgical process used in extractive metallurgy to extract metals from their ores. It involves heating the metallic compound, typically an oxide, with a reducing agent like carbon. The reducing agent removes the oxygen from the metal compound, leaving the metal in an uncombined form. This process is crucial for obtaining pure metals from their naturally occurring compounds.

For example, in the smelting reduction of zinc oxide (ZnO) by carbon monoxide (CO), the zinc oxide is heated to high temperatures. The carbon monoxide acts as a reducing agent, combining with the oxygen from the zinc oxide to form carbon dioxide, and leaving behind metallic zinc. This reaction requires external heat to maintain the necessary temperature for the process to occur efficiently.12

Reduction smelting is a key step in obtaining many common metals, including iron, zinc, and lead, from their respective ores.13