Kinetics of the electrochemical process of galena electrodes in the diethyldithiocarbamate solution

Abstract

The electrochemical process of galena in a pH 12.8 buffer solution was investigated using chronoamperometry and chronopotentiometry. To establish kinetic parameters on the surface of galena in the diethyldithiocarbamate solution, the exchange current density and the dependence of current density on reaction time were determined. Experimental results demonstrate that the exchange current density of galena is 1.585×10⁻² A/m² in the diethyldithiocarbamate-free solution. In the diethyldithiocarbamate solution, the thickness of lead diethyldithiocarbamate adsorbed on the surface of galena is 3.28 molecular layers, the diffusion coefficient of diethyldithiocarbamate on the surface of galena electrodes is 1.13×10⁻¹⁰ m²/s, and the exchange current density of galena is 0.45 A/m². Lead diethyldithiocarbamate on the surface of galena is firmly adsorbed.

Keywords

galena / electrochemistry / flotation / kinetics

References

[1] Li Q., Qiu G.Z., Qin W.Q. Kinetics of electrochemical process of pyrite electrode in diethyldithiocarbamate solution. Min. Metall. Eng., 2001, 21(2): 30.

[2] Chermyshova I. Anodic processes on a galena (PbS) electrode in the presence of n-butyl xanthate studied FTIR-spectroelectrochemically. J. Phys. Chem. B, 2001, 105(34): 8185.

[3] Woods R. Electrochemical potential controlling flotation. Int. J. Miner. Process., 2003, 72, 151.

[4] Herrera-Urbina R., Sotillo F.J., Fuerstenau D.W. Effect of sodium sulfide additions on the pulp potential and amyl xanthate flotation of cerussite and galena. Int. J. Miner. Process., 1999, 55, 157.

[5] Gu G.H., Hu Y.H., Qiu G.Z., et al. Origin potential flotation of galena and its industrial application. Min. Metall. Eng., 2002, 22(4): 30.

[6] Muñoz J.A., Gómez C., Ballester A., et al. Electrochemical behaviour of chalcopyrite in the presence of silver and Sulfolobus bacteria. J. Appl. Electrochem., 1998, 28, 49.

[7] Lazaro I., Nicol M. J. A rotating ring-disk study of the initial stages of the anodic dissolution of chalcopyrite in acidic solutions. J. Appl. Electrochem., 2006, 36, 425.

[8] Güler T., Hiçyllmaz C., Gökağaç G., Ekmekçi Z. Electrochemical behaviour of chalcopyrite in the absence and presence of dithiophosphate. Int. J. Miner. Process., 2005, 75, 217.

[9] Cai D.C. Electrochemical Research Methods, 2005 Chengdu, Electronic Science and Technology University Press, 83.

[10] Bard A.J., Faulkner L.R. Electrochemical Methods, 2001 2nd Ed New York, John Wiley & Sons Inc., 102.

[11] Gu Z., Dai C.S., Chen L. Electrochemical Measurements, 2006 Beijing, Chemical Industry Press, 106.

[12] Cisneros-González I., Oropeza-Guzmán M.T., González I. Cyclic voltammetry applied to the characterization of galena. Hydrometallurgy, 1999, 53, 133.

[13] Noda Y., Ohba S., Sato S., Saito Y. Charge distribution and atomic thermal vibration in lead chalcogenide crystals. Acta Crystallogr. B, 1983, 39, 312.

[14] Iwasaki H., Hagihara H. The crystal structure of lead ( II) diethyldithiocarbamate. Acta Crystallogr. B, 1972, 28, 507.

[15] Wang D.Z., Gu G.H., Liu R.Y. Potential adjustment flotation of galena-lime-diethyldithiocarbamate system. Chin. J. Nonferrous Met., 1998, 8(2): 322.