Satbayev University, Almaty, Kazakhstan

N. K. Dosmukhamedov, Professor, Department of Metallurgy and Mineral Processing, e-mail: nurdos@bk.ru
Zh. A. Yussupova*, Doctoral Student, Department of Metallurgy and Mineral Processing, e-mail: zhanar.yussupova@flmidth.com

Weizmann Institute of Science, Rehovot, Israel
V. A. Kaplan, Academic Consultant, Department of Material and Interfaces, e-mail: valery.kaplan@weizmann.ac.il

Zhezkazgan University named after O. A. Baikonurov, Zhezkazgan, Kazakhstan
E. E. Zholdasbay, Associated Professor, Head of Department of Mining, Metallurgy and Natural Sciences

*Correspondence author.

The possibility of processing of 1.09 g/t gold content ore from Central Kazakhstan by cyanidation on activated carbon has been studied. The results of studies on ore phase composition are presented: the total amount of cyanidable gold in the sample is 80.59%; the share of refractory gold not recoverable by direct cyanidation is 19.41% of the total mass of metal; the total share of free gold with clean surface at ore size of 95% grade –0.071 mm is 36.78%. Based on the results of Preg Robbing Adsorption Kinetics test, the preg robbing property of ore is established. It was found that during the ore cyanidation process, the dissolved gold has a reverse deposition effect on the ore. It is shown that when the contact time of ore with solution is increased up to 60 min, the gold allocation to ore components increases from 23 to 50%. Experiments on cyanidation of ore on activated carbon in CIP and CIL modes in a bottle-type agitator at sodium cyanide flow rates of 0.5 kg/t, 0.75 kg/t and 1.25 kg/t were carried out. Norit RO 3515 activated carbon was used as a sorbent. In all experiments CaO was added to the leaching solution at the rate of 1.2 kg/t. The acidity of the solution was maintained at pH = 11.5. On the basis of comparative test results in CIP and CIL modes the superiority of ore cyanidation in CIL mode is shown. The optimal parameters of ore cyanidation in CIL mode were established: duration = 12 hours; NaCN consumption = 0.5 kg/t; acidity pH = 11; oxygen concentration in the solution 11.5 mg/l. Gold recovery in solution was more than 77%. 

1. Marsden J. O., House C. I. The Chemistry of Gold Extraction. 2^nd ed. Society for Mining. Metallurgy & Exploration (SME), 2006. pp. 297–364.
2. Laitos J. G. The Current Status of Cyanide Regulations: Memories of Past Disasters Reinforce Present-Day Fears. Engineering and Mining Journal. 2012. Vol. 213, Iss. 2. pp. 34–40.
3. Ofori-Sarpong G. O., Adam A.-S., Amankwah R. K. Detoxification of Cyanide Wastewater by Cyanotrophic Organisms: the Case of Phanerochaete Chrysosporium. Ghana Mining Journal. 2020. Vol. 20, Iss. 1. pp. 34–44.
4. Kaksonen A. H., Boxall N. J., Gumulya Y., Khaleque H. N., Morris C., Bohu T., Cheng K. Y., Usher K. M., Lakaniemi A.-M. Recent Progress in Biohydrometallurgy and Microbial Characterisation. Hydrometallurgy. 2018. Vol. 180. pp. 7–25.
5. Thompson P., Runge K., Dunne R. C. Sulfide Flotation testing. In: Mineral Processing and Extractive Metallurgy Handbook, Vols. 1, 2. Society for Mining, Metallurgy & Exploration (SME), 2019. pp. 1029–1031.
6. Manning T. J., Kappes D. W. Heap Leaching of Gold and Silver Ores. In: Gold Ore Processing (2^nd ed.). Elsevier Science, 2016. pp. 413–428.
7. Medina D., Anderson C. G. A Review of the Cyanidation Treatment of Copper-Gold Ores and Concentrates. Metals. 2020. Vol. 10, Iss. 7. 897.
8. Ding J., Ye S. F. Research on Gold Recovery from Residue of Roasting-Cyaniding Process by Chloridizing Roast. Gold Science and Technology. 2014. Vol. 22, Iss. 4. pp. 113–117.
9. Zhang Y.-L., Li H.-M., Yu X.-J. Fe Extraction from High-Silicon and Aluminum Cyanide Tailings by Pretreatment of Water Leaching Before Magnetic Separation. Transactions of Nonferrous Metals Society of China. 2013. Vol. 23, Iss. 4. pp. 1165–1173.
10. Gong C. Process Study on Iron and Gold Recovery from Cyanide Tailings: Master’s Thesis. Changsha: Central South University, 2014.
11. Celep O., Altinkaya P., Yazici E. Y., Deveci H. Thiosulphate Leaching of Silver from an Arsenical Refractory Ore. Minerals Engineering. 2018. Vol. 122. pp. 285–295.
12. Hilson G., Monhemius A. J. Alternatives to Cyanide in the Gold Mining Industry: What Prospects for the Future? Journal of Cleaner Production. 2006. Vol. 14, Iss. 12-13. pp. 1158–1167.
13. Kholov K. I.; Sharifboev N. T., Samikhov S. R., Dzhurakulov S. R., Zarifova M. S. Gold Leaching by Various Solutions, Alternative of Cyanide and Their Prospects in the Future. Journal of Siberian Federal University. Engineering & Technologies. 2021. Vol. 14, Iss. 4. pp. 433–447.
14. Ghobadi B., Noaparast M., Shafaei S. Z., Unesi M. Optimization of Cyanidation Parameters to Increase the Capacity of Aghdarre Gold Mill. Journal of Mining and Environment. 2014. Vol. 5, Iss. 2. pp. 121–128.
15. Adams M. D. Gold Ore Processing: Project Development and Operations. 2^nd ed. Elsevier Science, 2016. pp. 525–531.
16. Goodal W. R., Leatham J. D., Scales P. J. A New Method for Determination of Preg-Robbing in Gold Ores. Minerals Engineering. 2005. Vol. 18, Iss. 2. pp. 1135–1141.
17. de Andrade Lima L. R. P. Dynamic Simulation of the Carbon-in-Pulp and Carbon-in-Leach Processes. Brazilian Journal of Chemical Engineering. 2007. Vol. 24, Iss. 4. pp. 623–635.
18. Vorster B. J., Flatman S. R. Cyanide Control in the Metallurgical Process of Gold Extraction in AngloGold (S. A.). The Journal of The Southern African Institute of Mining and Metallurgy. 2001. Vol. 101, Iss. 7. pp. 359–365.