SOLUBILIZATION OF MANGANESE FROM ORES BY HETEROTROPHIC MICROORGANISMS

The potential for using heterotrophic micro-organisms to solubilize manganese from low-grade domestic ores is being assessed at the Reno Research Center, U.S. Bureau of Mines. More than 90% of the manganese has been extracted from a variety of oxide ores in shake-flask tests using molasses as a source of nutrients for the micro-organisms. It has also been demonstrated that high recoveries of manganese can be obtained from a domestic wad ore using column bioleaching. The isolation and identification of organisms responsible for manganese extraction are discussed, as are the mechanisms responsible for manganese solubilization.