MICROORGANISMS AS CHEMICAL REAGENTS - THE HEMATITE SYSTEM

Microorganisms can function as flocculating agents, flotation modifiers and flotation collectors. Thus, they can take the place of chemical reagents in mineral processing and hydrometallurgy operations and, therefore, can be themselves considered as reagents. For example, a microorganism should function somewhat as a chemical flocculant if it is to some degree hydrophobic and can attach itself in some manner, such as though electrostatic interaction, to the fine mineral particles to be flocculated. In addition, hydrophobic microorganisms should render a hydrophilic mineral surface somewhat hydrophobic if they attach themselves to the mineral surface. A previously non-floatable mineral can in this manner be rendered floatable. The present paper investigates the principles of the use of a hydrophobic, highly negatively charged, bacterium, Mycobacterium phlei, as a flocculating agent for finely divided hematite suspensions and as a flotation collector for hematite.