Kola MMC, Monchegorsk, Russia

G. E. Naumenko, Chief Engineer, Chemical and Metallurgical Shop, e-mail: NaumenkoGE@kolagmk.ru
D. E. Nikolaev, Senior Technologist, Chemical and Metallurgical Shop, e-mail: NikolaevDE@kolagmk.ru
A. V. Shevtsov, Chief Specialist, Hydrometallurgical Department of the Scientific and Technical Center, e-mail: ShevcovAV@kolagmk.ru
P. V. Smirnov, Chief Manager, Scientific and Technical Center, e-mail: Smirnov1PV@kolagmk.ru

For JSC Kola MMC, as one of the largest nickel producers, in the conditions of the predicted surplus of this metal, the necessary conditions for stable development and strengthening of the presence in the nickel market are increasing production efficiency and diversifying the range of commercial products. The attention of manufacturers and researchers around the world in 2025 is focused on the rapidly growing sector of nickel consumption, namely: the battery industry, since nickel is one of the main components in the synthesis of precursors of cathode materials for lithium-ion batteries (LIB). At the same time, the main source of nickel in the production of LIB precursors is nickel sulfate. During large-scale laboratory experiments it was established that electrochemical dissolution of edge trimmings of the highest commercial grades of cathode nickel of JSC Kola MMC in sulfuric acid of own production, followed by vacuum evaporation and crystallization during cooling, allows for obtaining a mixture of hexa- and heptahydrate nickel sulfates that meets the impurity content requirements for grade Ch. The achieved indicators are confirmed by the results of chemical analysis in two laboratories. The laboratory results have been successfully tested on an industrial scale, resulting in the creation of a process for the production of commercial grade Ch nickel sulfate, which is in demand on the domestic market. The presented technology is patented and includes electrochemical dissolution of cathode trimmings, vacuum evaporation, isohydric crystallization, centrifugation to separate the mother liquor and washing of the commercial salt. There are prospects for improving the quality of the resulting nickel sulfate to battery grade. The introduction of nickel sulfate production at JSC Kola MMC did not require any additional equipment costs. The economic effect of the procedure was estimated at an additional premium of $3,500 to the price of nickel on the London Non-Ferrous Metals Exchange (LME).

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