Gipronikel Institute LLC, Saint Petersburg, Russia

D. M. Bogatyrev, Researcher at the Pyrometallurgy Laboratory, e-mail: BogatyrevDM@nornik.ru
L. B. Tsymbulov, Director of the Research and Development Department, Corresponding Member of the Russian Academy of Natural Sciences, Doctor of Technical Sciences, Professor, e-mail: TsymbulovLB@nornik.ru
S. S. Ozerov, Lead Researcher at the Pyrometallurgy Laboratory, Candidate of Technical Sciences, e-mail: OzerovSS@nornik.ru

This paper describes the results of a study that looked at the behavior of noble metals during oxidizing smelting of copper-nickel sulphide concentrate under conditions simulating the Vanyukov process. The known relationship was confirmed between the specific consumption of oxygen and the composition of the resulting matte. The effect of the matte composition on the yield was also considered. The results of the conducted study indicate the predominant concentration of noble metals in the matte phase. Based on the chemical analysis of the obtained samples of mattes and slags, the authors calculated how the noble metals were distributed between the smelting products, and examined the effect of the composition of the obtained mattes on the distribution coefficients. The calculated distribution coefficients were compared with the known production data. The range of the calculated distribution coefficients was found to increase in the following row: Ag → Au → Ru → Ir → Pt (Pd, Rh). Having analyzed some hardened slag samples by scanning electron microscopy and electron microprobe analysis (SEM – EMPA), the authors established a probable distribution of forms in which noble metals can get wasted. The data collected from SEM – EMPA of slag indicate a possible presence of gold in the iron-silicate melt, which comes in the form of metallic solubility. Based on the conducted studies, recommendations were formulated on how to carry out the oxidizing smelting process to ensure minimal losses of noble metals with slags.

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