Adjustment of electrode processes to build up contrast processing characteristics of sulfides

The article describes the studies into generation of contrast electrochemical characteristics of sulfides during oxidation–reduction processes in milling cycle with the pyrite– iron micro galvanic coupling and with monitoring and adjustment of electrode processes. The oxidation and oxygen absorption kinetics of pyrite in milling is studied, and the concentration of sulfur-containing anions in oxidation of pyrite in the pH range of 6–14 is presented. It is found that the highest absorption of oxygen by pyrite takes place in the high-alkali environment (pH 12). With the increasing alkalinity of the medium, the concentration of sulfur-containing anions grows by a few factors, and this is true particularly for thiosulfate ions (S2O3 2–) where floatability of pyrite decreases. The experimental measurements of electrode potentials of pyrite and steel electrodes reveal correlation between the processing conditions, values of electrode potentials and floatability of sulfides and quartz. The values of the potentials depend on the pH and on the concentration of modifiers. The largest difference between the potentials happens at pH 11 and is 600 mV as against the values of the potentials at pH 7 and 9, which governs pyrite suppression and affects selective flotation. The influence of the metallic iron powder as the milling environment on the floatability of sulfide minerals (FeS2, CuFeS2, ZnS) and SiO2 in the presence of different modifiers at pH 7 and 11. The long-time milling (> 60 min) induces intense oxidation of sulfide minerals and milling iron (>2 kg/t), which activates flotation of pyrite and reduces quality of concentrates. With the increasing concentrate of sodium sulfate, the pyrite electrode potential grows in the negative range at рН ≥ 9–11, which goes with the reduction in pyrite extraction.

Keywords: iron, pyrite, pyrrhotine, electrochemistry, electrode, potential, oxidation, contrast, flotation.
For citation:

Bocharov V. А., Ignatkina V. A., Abrytin D. V., Kayumov А. А., Kayumova V. R. (Korzh). Adjustment of electrode processes to build up contrast processing characteristics of sulfides. MIAB. Mining Inf. Anal. Bull. 2022;(10):39-50. [In Russ]. DOI: 10.25018/ 0236_1493_2022_10_0_39.


The study was supported by the Russian Foundation for Basic Research, Project No. 20-05-00157.

Issue number: 10
Year: 2022
Page number: 39-50
ISBN: 0236-1493
UDK: 622.765
DOI: 10.25018/0236_1493_2022_10_0_39
Article receipt date: 20.07.2022
Date of review receipt: 15.08.2022
Date of the editorial board′s decision on the article′s publishing: 10.09.2022
About authors:

V.A. Bocharov1, Dr. Sci. (Eng.), Professor, e-mail:, ORCID ID: 0000-0002-8233-9635,
V. A. Ignatkina1, Dr. Sci. (Eng.), Professor, e-mail:, ORCID ID: 0000-0003-2552-206X
D.V. Abrytin, Cand. Sci. (Eng.), Deputy General Director, OOO «ADV-Inzhiniring», e-mail:,
A.A. Kayumov1, Cand. Sci. (Eng.), Senior Process Engineering, e-mail:, ORCID ID: 0000-0003-0502-6595,
V.R. Kayumova (Korzh)1, Graduate Student, e-mail:, ORCID ID: 0000-0001-7527-1284,
1 National University of Science and Technology «MISiS», 119049, Moscow, Russia.


For contacts:

A.A. Kayumov, e-mail:


1. Leja J. Electrical characteristics of interfaces. Electrical double layer and zeta potential. Surface Chemistry of Froth Flotation. Plenum Press, New York, 1982, pp. 433—492. DOI: 10.1007/978-1-4615-7975-5_7.

2. Ignatkina V. A., Bocharov V. A., Aksenova D. D., Kayumov A. A. Zeta potential of the surface of ultrafine sulfides and floatability of minerals. Izvestiya Vuzov. Tsvetnaya Metallurgiya. 2017, no. 1, pp. 4—11. [In Russ]. DOI: 10.17073/0021-3438-2017-1-4-12.

3. Sorokin M. M. Flotatsiya. Modifikatory. Fizicheskie osnovy. Praktika [Flotation. Modifiers. Physical basics. Practice], Moscow, MISiS, 2016. 372 p.

4. Moslemi H., Gharabaghi M. A review on electrochemical behavior of pyrite in the froth flotation process. Journal of Industrial and Engineering Chemistry. 2017, vol. 47, pp. 1—18. DOI: 10.1016/j.jiec.2016.12.012.

5. Pozzo R. L., Iwasaki I. Pyrite-pyrrhotite grinding media interactions and their effects on media wear and flotation. Journal of The Electrochemical Society. 1989, vol. 136, no. 6, pp. 1734—1740. DOI: 10.1149/1.2097001.

6. Zhao Cao, Peng Wang, Wen-Bo Zhang, Xiao-Bo Zeng, Yong-Dan Cao Mechanism of sodium sulfide on flotation of cyanide-depressed pyrite. Transactions of Nonferrous Metals Society of China. 2020, vol. 30, no. 2, pp. 484—491. DOI: 10.1016/s1003-6326(20)65228-1.

7. Bao Guo, Yongjun Peng, Gretel Parker Electrochemical and spectroscopic studies of pyrite–cyanide interactions in relation to the depression of pyrite flotation. Minerals Engineering. 2016, vol. 92, pp. 78—85. DOI: 10.1016/J.MINENG.2016.03.003.

8. Ejtemaei M., Nguyen A. V. Characterisation of sphalerite and pyrite surfaces activated by copper sulphate. Minerals Engineering. 2017, vol. 100, pp. 223—232. DOI: 10.1016/J. MINENG.2016.11.005.

9. Nicol M. The electrochemistry of chalcopyrite in alkaline solutions. Hydrometallurgy. 2019, vol. 187, pp. 134—140. DOI: 10.1016/j.hydromet.2019.05.016.

10. Plaksin I. N., Shafeev R. Sh., Chanturiya V. A. The relationship of the energy structure of mineral crystals with their flotation properties. Trudy VIII Mezhdunarodnogo kongressa po obogashcheniyu poleznykh iskopaemykh. T. 2 [Proceedings of the VIII International Congress on Mineral Enrichment, vol. 2] Leningrad, Mekhanobr, 1969, pp. 235—245. [In Russ].

11. Hu Yue-Hua, Sun Wei Electrochemistry of flotation of sulfide minerals. Beijing: Tsinghua University Press, 2009, 306 p.

12. Dan Liu, Yi-Jie Wang, Yong-Jun Xian, Shu-Ming Wen Electronic structure and flotability of gold-bearing pyrite. A density functional theory study. Journal of Central South University. 2017, vol. 24, pp. 2288–2293. DOI: 10.1007/S11771-017-3640-4.

13. Kakovskiy I. A. On the kinetics of oxidation of mixtures of sulfide minerals by oxygen in aqueous solutions. Obogashchenie Rud. 1980, no. 3, pp. 3—6. [In Russ].

14. Mitrofanov S. I., Ryskin M. Ya. Electrochemical properties of minerals and adsorption of collecting reagents. Trudy VIII Mezhdunarodnogo kongressa po obogashcheniyu poleznykh iskopaemykh. T. 2 [Proceedings of the VIII International Congress on Mineral Enrichment, vol. 2], Leningrad, Mekhanobr, 1969, pp. 270—280. [In Russ].

15. Chanturiya V. A., Vigdergauz V. E. Elektrokhimiya sul'fidov. Teoriya i praktika flotatsii [Electrochemistry of sulfides. Theory and practice of flotation], Moscow, Ruda i metally, 2008, 272 p.

16. Abramov A., Önal G., Dogan Z. Physico-chemical models for activation, flotation and depression of pyrite in copper flotation. Mineral Processing on the Verge of the 21st Century. 2017. DOI: 10.1201/9780203747117.

17. Nicol M., Suchun Zhang, Tjandrawan V. The electrochemistry of pyrite in chloride solutions. Hydrometallurgy. 2018, vol. 178, pp. 116—123. DOI: 10.1016/j.hydromet.2018.04.013.

18. Dongping Tao, Yue Wang, Lin Li An electrochemical study of surface oxidation and collectorless flotation of pyrite. International Journal of Electrochemical Science. 2018, vol. 13, pp. 5971—5982. DOI: 10.20964/2018.06.32.

19. Buswell A. M., Nicol M. J. Some aspects of the electrochemistry of the flotation of pyrrhotite. Journal of Applied Electrochemistry. 2002, vol. 32, pp. 1321–1329. DOI: 10.1023/A: 1022664310845.

20. Alireza Javadi Sulphide minerals: surface oxidation and selectivity in complex sulphide ore flotation. Doctoral thesis. October 2015. Luleå University of Technology, Sweden. 48 p.

21. Kakovskiy I. A., Kosikov V. M. On the quantitative assessment of the kinetics of oxidation of sulfide minerals in solution. Obogashchenie Rud. 1974, no. 1, pp. 28—31. [In Russ].

22. Yianatos J., Carrasco C., Vinnett L., Rojas I. Pyrite recovery mechanisms in rougher flotation circuits. Minerals Engineering. 2014, vol. 66–68, pp. 197–201. DOI: 10.1016/j. mineng.2014.03.020.

23. Zhao Cao, Xumeng Chen, Yongjun Peng The role of sodium sulfide in the flotation of pyrite depressed in chalcopyrite flotation. Minerals Engineering. 2018, vol. 119, pp. 93–98. DOI: 10.1016/j.mineng.2018.01.029.

24. Yasemin Öztürk, Özlem Bıçak, Elif Özdemir, Zafir Ekmekçi Mitigation negative effects of thiosulfate on flotation performance of a Cu-Pb-Zn sulfide ore. Minerals Engineering. 2018, vol. 122, pp. 142—147. DOI: 10.1016/j.mineng.2018.03.034.

25. Yufan Mua, Yongjun Peng, Lauten R. A. The depression of pyrite in selective flotation by different reagent systems — A Literature review. Minerals Engineering. 2016, vol. 96—97, pp. 143—156. DOI: 10.1016/j.mineng.2016.06.018.

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