World Environment
p-ISSN: 2163-1573 e-ISSN: 2163-1581
2012; 2(6): 110-115
doi: 10.5923/j.env.20120206.01
N. Pradhan 1, R. R. Nayak 2, D. K. Mishra 1, E. Priyadarshini 1, L. B. Sukla 1, B. K. Mishra 1
1Institute of Minerals and Materials Technology, Council of Scientific & Industrial Research (CSIR), Bhubaneswar, 751013, India
2Indian Institute of Chemical Technology, Council of Scientific & Industrial Research (CSIR), Hyderabad, 500 007, India
Correspondence to: L. B. Sukla , Institute of Minerals and Materials Technology, Council of Scientific & Industrial Research (CSIR), Bhubaneswar, 751013, India.
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This study aims at studying effect of anaerobic dissimilatory iron (III) reducing bacterial consortium on different phases of iron present in lateritic nickel ore. Such conversion in lateritic nickel ore are helpful in better recovery of sorbed metal values like Ni and Co by subsequent bioleaching or acid leaching. Here properties of thermally and microbially reduced lateritic nickel ore are compared vis-à-vis original ore. An anaerobic dissimilatory iron (III) reducing bacterial consortium capable of using glucose as carbon source and lateritic nickel ore as terminal electron acceptor was used for microbial reduction of ore under anaerobic condition. Microbial reduction changes the initial light brown colour of the lateritic nickel ore to dark brown. The change in colour is due to the conversion of goethite to magnetite, which is confirmed from the XRD pattern. The FTIR spectra and the UV-Visible spectra support the presence both goethite and hematite. The study shows that changes in phases brought about by microbial treatment are different than those by thermal treatment. The carrier mediated exchange interaction between Fe2+ and Fe3+ ions in lateritic nickel ore sample treated with IRB consortium is responsible for higher ferromagnetic ordering. The thermal reduction of the same sample showed lowering of ferromagnetic ordering due to the decreasing percentage of Fe2+ and Fe3+ ions.
Keywords: Iron Reducing Bacteria, Lateritic Ore, Goethite, Magnetite, Magnetic Properties
Cite this paper: N. Pradhan , R. R. Nayak , D. K. Mishra , E. Priyadarshini , L. B. Sukla , B. K. Mishra , "Microbial Treatment of Lateritic Ni-ore for Iron Beneficiation and Their Characterization", World Environment, Vol. 2 No. 6, 2012, pp. 110-115. doi: 10.5923/j.env.20120206.01.
![]() | Figure 1. Gram staining of iron reducing bacterial consortia |
![]() | Figure 2. SEM image showing needle shaped goethite particles (G), bacterial bio-film (BF), Iron reducing bacteria (IRB) and granular magnetite particles (M) in close association with ore particles |
![]() | Figure 3. Release of Fe (II) ion in medium and change in pH during growth |
![]() | Figure 4. XRD pattern of original nickel laterite ore and IRB treated samples. H: Hematite (Fe2O3); G: Goethite (FeOOH); M: Magnetite (Fe3O4) |
![]() | Figure 5. UV-visible spectrum of original nickel laterite ore and IRB treated samples |
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![]() | Figure 6. Hysteresis loop curve for all the samples |
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