Preparation of rhodium concentrate from gold cementate

This article describes studies on improving reprocessing technology gold production cementate (GPC) formed in refining section of chemical metallurgical shop at JSC Uralelektromed, in order to increase the extraction rate of targeted metals into marketable products, diversification of production, achievement of economic effect due to increasing content of precious metals (PM) in individual concentrates. The optimization of GPC reprocessing technology includes intensification of leaching of initial material and filtration of produced pulp, in order to increase the extraction of gold and platinum group metals (PGM) into solution and decrease the circulated PM. This would allow individual products (crude PM) to be obtained with minimum material loss and labor consumption. It is possible to increase rhodium content in concentrate and to reduce its circulation by preliminary oxidating annealing at the temperature above 500 °C. At this temperature hardly soluble trioxide Rh₂O₃ is formed on rhodium surface, insoluble in aqua regia, thus allowing it to deposit in the form of individual product. The influence of temperature and composition of gaseous phase was established upon oxidizing annealing of initial raw stuff (t = 500÷750 °C) on the composition of rhodium trioxide concentrate (15÷45 % Rh₂O₃). Reprocessing flowchart of gold production cementate was developed and tested on commercial scale, allowing for the simultaneous production of several products: deposited gold (Au ≥ 98 %), deposited silver (Ag ≥ 98 %), PGM concentrate (Pt ≥ 45 % and Pd ≥ 15 %), rhodium concentrate (Rh = 15÷45 %).

1. Nagai H., Shibata E., Nakamura T. Development of methods for concentration and dissolution of Rh and Ru from copper slime. Hydrometallurgy. 2017;169:282—289. https://doi.org/10.1016/j.hydromet.2017.01.004

2. Crundwell F.K., Moats M.S., Ramachandran V., Robinson T.G., Davenport W.G. Extractive metallurgy of nickel, cobalt and platinum group metals. Chapter 37. Refining of the platinum-group metals. Elsevier Ltd., 2011. P. 489—534. https://doi.org/10.1016/C2009-0-63541-8

3. Nakhjiri A.T., Sanaeepur H, Amooghin A.E., Shirazi M.M.A. Recovery of precious metals from industrial wastewater towards resource recovery and environmental sustainability: A critical review. Desalination. 2022;527:115510. https://doi.org/10.1016/j.desal.2021.115510

4. Hayashibe Y. Reference module in chemistry, molecular sciences and chemical engineering. In: Precious Metals. Elsevier Ltd., 2005. P. 277—287.

5. Мастюгин С.А., Волкова Н.А., Набойченко С.С., Ласточкина М.А. Шламы электролитического рафинирования меди и никеля. Екатеринбург: УрФУ, 2013. 256 с.

6. Mulwanda J., Dorfling C. Recovery of dissolved platinum group metals from copper leach solutions by precipitation. Minerals Engineering. 2015;80:50—56. https://doi.org/10.1016/j.mineng.2015.07.002

7. Boduen A.Y., Fokina S.B., Polezhaev S.Yu. The hydrometallurgical pretreatment of a refractory gold sulfide concentrate. In: Innovation-based development of the mineral resources sector: challenges and prospects: Proceedings of the 11th Russian-German raw materials conference (Potsdam, Germany, 7—8 Nov. 2018). London: CRC Press, 2018. P. 331—340. https://doi.org/10.1201/9780429022388

8. Королев А.А., Краюхин С.А., Мастюгин С.А., Гибадуллин Т.З., Лебедь А.Б. Способ получения серебра и металлов платиновой группы: Пат. 2680552 (РФ). 2018.

9. Zotova I.E. , Fokina S.B., Boduen A.Ya., Petrov G.V. Sorption concentration of ruthenium from sulfuric solutions. Non-Ferrous Metals. 2019;(1):12—15. https://doi.org/10.17580/nfm.2019.01.02

10. Aghaei E., Alorro R.D., Encila A.N., Yoo K. Magnetic adsorbents for the recovery of precious metals from leach solutions and wastewater. Metals. 2017;7(12):529. https://doi.org/10.3390/met7120529

11. Aleksandrova T.N., O’Connor C. Processing of platinum group metal ores in Russia and South Africa: current state and prospects. Journal of Mining Institute. 2020;244:462—473. (In Russ.). https://doi.org/10.31897/PMI.2020.4.9

12. Jacek Sitko. Analysis of selected technologies of precious metal recovery processes. Multidisciplinary Aspects of Production Engineering 2019;2(1):72—80. https://doi.org/10.2478/mape-2019-0007

13. Kobylyanski A., Zhukova V., Petrov G., Boduen A. Challenges in processing copper ores containing sulfosalts. In: Scientific and practical studies of raw material issues: Proceedings of the Russian-German raw materials dialogue: A collection of young scientists papers and discussion (19 Nov. 2019). London: CRC Press, 2020. P. 120—126. https://doi.org/10.1201/9781003017226-18

14. Лебедь А.Б., Мальцев Г.И., Мамяченков С.В. Аффинаж золотосеребряных сплавов на ОАО «Уралэлектромедь». Екатеринбург: УрФУ, 2015. 159 с.

15. Лебедь А.Б., Скороходов В.И., Кремко Е.Г., Волкова Н.А., Мастюгин С.А., Горяева О.Ю., Рычков Д.М. Способ выделения платиновых металлов: Пат. 2111272 (РФ). 1998.

16. Polvanov S., Ergashev N., Khodzhiev M., Tashmuratov A. Study of obtaining accompanying elements in the processing of gold-bearing ores of the muruntau deposit. Universum: Engineering Sciences. 2022;7(100):20—24. https://doi.org/10.32743/UniTech.2022.100.7.14079

17. Кононова О.Н., Мельников А.М., Борисова Т.В. Способ разделения платины (II, IV), родия (III) и никеля (II) в хлоридных растворах: Пат. 2527830 (РФ). 2010.

18. Гинзбург С.И., Езерская Н.А., Прокофьева И.В., Федоренко Н.В., Шленская В.И., Бельский Н.К. Аналитическая химия платиновых металлов. М.: Наука, 1972. 616 с.

19. Плеханов К.А., Ашихин В.В., Шевелева Л.Д., Лебедь А.Б., Краюхин С.А., Скопин Д.Ю. Способ выделения платиновых металлов: Пат. 2238244 (РФ). 2002.

20. Huang Z.S., Yang T.Z. Comparative study on refractory gold concentrate kinetics and mechanisms by pilot scale batch and continuous bio-oxidation. Minerals. 2021;11(12):1343. https://doi.org/10.3390/min11121343

21. Rinne M., Elomaa H., Seisko S., Lundstrom M. Direct cupric chloride leaching of gold from refractory sulfide ore: process simulation and life cycle assessment. Mineral Processing and Extractive Metallurgy Review. 2021;43(5):598—609. https://doi.org/10.1080/08827508.2021.1910510

22. Масленицкий И.Н., Чугаев Л.В. Металлургия благородных металлов. М.: Металлургия, 1987. 432 с.

23. Меретуков М.А., Орлов А.М. Металлургия благородных металлов. Зарубежный опыт. М.: Металлургия, 1991. 416 с.

24. Kepp K.P. Chemical causes of metal nobleness. ChemPhysChem. 2020;21(5):360—369. https://doi.org/10.1002/cphc.202000013

25. Федоров И.А. Родий. М.: Наука, 1966. 276 с.

26. Бимиш Ф. Аналитическая химия благородных металлов. Пер. с англ. под ред. С.И. Гинзбург. М.: Мир, 1969. 592 с.

27. Kunimori K., Oyanagi H., Shindo H., Ishigaki T., Uchijima T. Structural transformation and catalytic behaviors of rhodium ternary oxides during calcination and reduction treatments. Studies in Surface Science and Catalysis. 1993;75:2039—2042. https://doi.org/10.1016/S0167-2991(08)64220-2

28. Šarić A., Popović S., Trojko R., Music S. The thermal behavior of amorphous rhodium hydrous oxide. Journal of Alloys and Compounds. 2001;320(1):140—148. https://doi.org/10.1016/S0925-8388(01)00938-0

29. Barclay G.A., Broadbent R.F., Kingston J.V., Scollary G.R. The thermal behaviour of some rhodium complexes. Thermochimica Acta. 1974;10(1):73—83. https://doi.org/10.1016/0040-6031(74)85025-2

30. Nitsenko A.V., Volodin V.N., Linnik X.A., Tuleutay F.K., Burabaeva N.M. Distillation recovery of tellurium from copper telluride in oxide forms. Izvestiya. Non-Ferrous Metallurgy. 2022;28(4):45—54. (In Russ.). https://doi.org/10.17073/0021-3438-2022-4-45-54