Influence of Chelators on Iron Solubilization from Quartz and Feldspars by Bioleaching


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Ultra-fine iron particles are difficult to treat by conventional mineral processing methods. Thus bioleaching is an attractive alternative for effective removal of iron minerals. The removal of oxidic Fe-phases from industrial silicates via bioleaching needs to be optimized with regard to the rate of iron reduction and dissolution. A new role for chelators as the low addition of AQDS or NTA during bacterial quality improvement of non-metallics, resulted in stimulating of Fe dissolution under non-controlled anaerobic conditions. AQDS stimulated bacterial iron reduction and Fe2+ concentration in solution was higher than Fe3+. However, NTA non-stimulated iron reduction, but increased bacterial iron dissolution in form of Fe3+. Changes in iron removal from samples were used to assess the chelator effectiveness of the heterotrophic bioleaching process. Chelators might be added to iron-contaminated non-metallics during bioleaching processes for stimulation of rate of iron removal.



Advanced Materials Research (Volumes 20-21)

Edited by:

Axel Schippers, Wolfgang Sand, Franz Glombitza and Sabine Willscher




I. Štyriaková, "Influence of Chelators on Iron Solubilization from Quartz and Feldspars by Bioleaching", Advanced Materials Research, Vols. 20-21, pp. 87-90, 2007

Online since:

July 2007




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