Characterization of Bacillus polymyxa from Jamnagar mine water and biobeneficiation of bauxite ore for iron through surface modification

摘要

Preliminary screening of the mine water sample from bauxite ore deposits in Jamnagar, India showed the presence of heterotrophic bacteria B.polymyxa. Growth conditions for the bacteria to bring about max. beneficiation were standardized by using the enriched Bromfield medium. B.polymyxa brought significant changes in the surface modifications of the mineral magnetite. The interaction resulted in surface chem. changes both on the cell and on the mineral surface by studying their electrophoretic mobility using Zeta meter 3.0. Dissoln. studies in the presence of microorganisms establish the foundation in which these processes could be used for the utility of beneficiation in the efficient sepn. of the impurities from the ore, thus confirmed that B.polymyxa has greater affinity towards magnetite and could be efficiently used to remove iron from magnetite. Expts. with respect to the bauxite ore was initiated after confirming the above result. Iron removal from bauxite ore by B.polymyxa has been demonstrated under 2​% sucrose concns. brought about 12.5​% removals in four days and under similar conditions the control in absence of B. polymyxa only 6​% iron removal was seen. Thus, B. polymyxa plays a significant role in biobenficiation of bauxite mineral. These observations clearly indicate that a direct mechanism through bacterial attachment to the ore and an indirect mechanism through leaching with metabolites are involved in the biobeneficiation process.