In situ characterization of natural pyrite bioleaching using electrochemical noise technique

Abstract

An in situ characterization technique called electrochemical noise (ECN) was used to investigate the bioleaching of natural pyrite. ECN experiments were conducted in four active systems (sulfuric acid, ferric-ion, 9k culture medium, and bioleaching solutions). The ECN data were analyzed in both the time and frequency domains. Spectral noise impedance spectra obtained from power spectral density (PSD) plots for different systems were compared. A reaction mechanism was also proposed on the basis of the experimental data analysis. The bioleaching system exhibits the lowest noise resistance of 0.101 MΩ. The bioleaching of natural pyrite is considered to be a bio-battery reaction, which distinguishes it from chemical oxidation reactions in ferric-ion and culture-medium (9k) solutions. The corrosion of pyrite becomes more severe over time after the long-term testing of bioleaching.

Keywords

bioleaching / pyrite / electrochemical noise / biological oxidation / chemical oxidation

References

[1] Vera M., Schippers A., Sand W. Progress in bioleaching: fundamentals and mechanisms of bacterial metal sulfide oxidation: part A. Appl. Microbiol. Biotechnol., 2013, 97(17): 7529.

[2] Liang Y.T., Zhu S., Wang J., Ai C.B., Qin W.Q. Adsorption and leaching of chalcopyrite by Sulfolobus metallicus YN24 cultured in the distinct energy sources. Int. J. Miner. Metall. Mater., 2015, 22(6): 549.

[3] Denise B., Heloisa A.A., Assis V.B., Oswaldo G. Electrochemical Techniques Used to Study Bacterial-Metal Sulfides Interactions in Acidic Environments, 2007 59.

[4] Ahmadi A., Khezri M., Abdollahzadeh A.A., Askari M. Bioleaching of copper, nickel and cobalt from the low grade sulfidic tailing of Golgohar Iron Mine, 2015, 154, 1.

[5] Mile D., Ana K., Visa T., Novica M. Influence of pyrometallurgical copper production on the environment. J. Hazard. Mater., 2009, 164(2-3): 892.

[6] Yin S.H., Wu A.X., Wang S.Y., Wang H.J. Simulation of solute transportation within porous particles during the bioleaching process. Int. J. Miner. Metall. Mater., 2010, 17(4): 389.

[7] Gu G.H., Sun X.J., Hu K.T., Li J.H., Qiu G.Z. Electrochemical oxidation behavior of pyrite bioleaching by Acidthiobacillus ferrooxidans. Trans. Nonferrous Met. Soc. China, 2012, 22(7): 1250.

[8] Mu Y.F., Peng Y.J., Lauten R.A. Electrochemistry aspects of pyrite in the presence of potassium amyl xanthate and a lignosulfonate-based biopolymer depressant. Electrochim. Acta, 2015, 174, 133.

[9] Constantin C.A., Chirita P. Oxidative dissolution of pyrite in acidic media. J. Appl. Electrochem., 2013, 43(7): 659.

[10] Sun H.Y., Chen M., Zou L.C., Shu R.B., Ruan R.M. Study of the kinetics of pyrite oxidation under controlled redox potential. Hydrometallurgy, 2015, 155, 13.

[11] Liu Y., Dang Z., Lu G.N., Wu P.X., Feng C.H., Yi X.Y. Utilization of electrochemical impedance spectroscopy for monitoring pyrite oxidation in the presence and absence of Acidithiobacillus ferrooxidans. Miner. Eng., 2011, 24(8): 833.

[12] Shi S.Y., Fang Z.H., Ni J.R. Electrochemical impedance spectroscopy of marmatite-carbon paste electrode in the presence and absence of Acidithiobacillus ferrooxidans. Electrochem. Commun., 2005, 7(11): 1177.

[13] Loto C.A. Electrochemical noise measurement technique in corrosion research. Int. J. Electrochem. Sci., 2012, 7, 9248.

[14] Wilson A.D., Baietto M. Applications and advances in electronic-nose technologies. Sensors, 2009, 9(7): 5099.

[15] Valentini C., Fiora J., Ybarra G. A comparison between electrochemical noise and electrochemical impedance measurements performed on a coal tar epoxy coated steel in 3% NaCl. Prog. Org. Coat., 2012, 73(2-3): 173.

[16] Mansfeld F., Chen C., Lee C.C., Xiao H. The effect of asymmetric electrodes on the analysis of electrochemical impedance and noise data. Corros. Sci., 1996, 38(3): 497.

[17] Bevilaqua D., Acciari H.A., Benedetti A.V., Fugivara C.S., Tremiliosi Filho G., Garcia O. Electrochemical noise analysis of bioleaching of bornite (Cu₅FeS₄) by Acidithiobacillus ferrooxidans. Hydrometallurgy, 2006, 83(1-4): 50.

[18] You G.X., Yu C.C., Lu Y., Dang Z. Evaluation of the protective effect of polysiloxane coating on pyrite with electrochemical techniques. Electrochim. Acta, 2013, 93, 65.

[19] Suresh G., Mudali U.K. Electrochemical noise analysis of pitting corrosion of type 304L stainless steel. Corrosion, 2014, 70(3): 283.

[20] Girija S., Mudali U.K. Electrochemical noise resistance evaluation of 304L SS in nitric acid and simulated nuclear high level waste. Corros. Eng. Sci. Technol., 2014, 49(5): 335.

[21] Tan Y.J. Understanding the effects of electrode inhomogeneity and electrochemical heterogeneity on pitting corrosion initiation on bare electrode surfaces. Corros. Sci., 2011, 53(5): 1845.

[22] Nieves-Mendoza D., Gaona-Tiburcio C., Hervert-Zamora H.L., Tobias R., Castro-Borges J. P., Colas R., Zambrano Robledo O. P., Martínez-Villafañe A., Almeraya-Calderón F. Statistical analysis of factors influencing corrosion in concrete structures. Int. J. Electrochem. Sci., 2012, 7(6): 5495.