Manganese minerals are widely distributed throughout the globe. The most important industrial uses of Mn are in the manufacture of steel, non-ferrous alloys, carbon-zinc batteries and some chemical reagents. Microbial recovery of manganese from low grade manganese ores using bioleaching was investigated in this paper. A bacterial strain, Staphylococcus epidermidis (MTCC-435) was collected from microbial type culture collection, IMTECH Chandigarh and used for the experiment. The experimental results for bioleaching with S. epidermidis showed that under pH 5.5, particle size –150 μm, pulp density 10%, temperature 35℃ and agitation 200 rpm, about 80% of Mn was recovered within 20 days of incubation.
A systematic study has been made to establish the reaction mechanism of bioleaching of manganese ore with the manganese reducing fungi, Penicillium citrinum, isolated from the top soil of an active manganese ore mine site. The fungi was utilised for dissolution of manganese from the low grade manganiferous ore. Leaching with the biomass free culture filtrate and with various acids such as oxalic, citric and sulphuric acid, provide a better insight to the process. On the basis of these studies, kinetic equations as a function of time is plotted to obtain appropriate conversion-time equation for leaching of manganese ore with bioacid and organic acid. The experimental values showed that the reaction is controlled by diffusion of the reactants through the permeable product layer.
Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights.