How is manganese monoxide made from manganese dioxide?

Manganese monoxide (MnO), also known as manganous oxide, is produced from manganese dioxide (MnO₂) through a reduction process. Commercially, this is achieved by passing carbon monoxide or hydrogen over manganese dioxide.1

In the broader context of manganese processing, the reduction of higher manganese oxides—such as MnO₂, Mn₂O₃, and Mn₃O₄—to manganous oxide is a standard step in smelting operations. This reduction is typically facilitated by carbon monoxide within a furnace environment.2