Role of corundum-adapted strains of Bacillus polymyxa in the separation ofhematite and alumina

Strains of Bacillus polymyxa, preadapted and grown in the presence of corun dum, were found to be capable of the efficient separation of hematite from alumina. Results of rests peformed using binary hematite-corundum and terna ry hematite-quartz-corundum mixtures in the presence of cells and metabolic products separated from the adapted bacterial culture indicated that more than 99% of the hematite could he efficiently separated through selective f locculation after desliming. It was found that alumina-specific bioproteins and other nonproteinaceous compounds were secreted by bacterial cells afte r adaptation to the mineral. The utility of this bioprocessing is demonstra ted in the removal of iron from bauxite ores through selective flocculation in the presence of the adapted bacteria.