ELECTROCHEMICAL AND BIOLEACHING STUDY OF CHALCOPYRITE (CuFeS2) WITH REDOX POTENTIAL CHANGES IN THE PRESENCE OF THE BACTERIA Acidithiobacillus ferrooxidans.

• Grant number: 10/13089-1
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2010
• End date: August 31, 2011
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Assis Vicente Benedetti
• Grantee: Fabiana Antonia Arena
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

In the present work will be performed a bioleaching and electrochemical study of chalcopyrite (CuFeS2) with variations in redox potential in the presence of Acidithiobacillus ferrooxidans bacteria. The potential variations of such systems are mainly resulting from the oxidation of Fe2+ to Fe3+ by the bacteria action. Both ferric ions, such as bacterial action contribute to the bioleaching of chalcopyrite (highly refractory sulfide mineral) that can be improved by controlling the potential of the system. Meanwhile, there is further study of the effect of electrochemical potential and if the potential established by another pair than the Fe3+ / Fe2+ can also have a beneficial effect on the dissolution of the mineral. Therefore, bioleaching studies at various concentrations of Fe2+ may allow assessment of bacterial action in the presence of chalcopyrite at different potential values. Simultaneously will evaluate solid waste generated in these trials, allowing the characterization of the main species formed during the process, and the role they play in the bioleaching of mineral sulphide mineral.Also will be used other pairs of redox potential near or above the couple Fe3+ / Fe2+ having the purpose of checking whether the bioleaching of chalcopyrite occurs simply by the action of the values of redox potential, or if it is necessary the presence of the pair Fe3+ / Fe2+ , or if compound is formed in the presence of Fe2+ which is responsible for more efficient solubilization of the mineral.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ARENA, FABIANA A.; SUEGAMA, PATRICIA H.; BEVILAQUA, DENISE; DOS SANTOS, ANA L. A.; FUGIVARA, CECILIO S.; BENEDETTI, ASSIS V.. Simulating the main stages of chalcopyrite leaching and bioleaching in ferrous ions solution: An electrochemical impedance study with a modified carbon paste electrode. MINERALS ENGINEERING, v. 92, p. 229-241, JUN 2016. (10/13089-1, 11/19868-5)