Kazakh National Research Technical University named after Kanysh Satpayev, Almaty, Republic of Kazakhstan:

E. G. Baykonurov, PhD student of a Chair “Metallurgical processes, heat engineering and special materials technology”, e-mail: erden_baikonurov@mail.ru
G. A. Usoltseva, Associated Professor of a Chair “Metallurgical processes, heat engineering and special materials technology”, e-mail: nota-vesna@yandex.ru

Moscow State University of Fine Chemical Technologies named after M. V. Lomonosov, Moscow, Russia:

O. V. Chernyshova, Assistant Professor of K. A. Bolshakov Chair “Chemistry and technology of rare and scattered elements, nanosized and composite materials”, e-mail: oxcher@mitht.ru
D. V. Drobot, Professor of K. A. Bolshakov Chair “Chemistry and technology of rare and scattered elements, nanosized and composite materials”, e-mail: dvdrobot@mail.ru

The paper proposes and justifies a technological scheme for electrochemical processing of the rhenium-containing heat-resistant ZhS32-VI (ЖС32-ВИ) alloy that contains, % (wt.): 4.0 Re; 9.3 Co; 8.6 W; 0.005 Y; 0.005 Lа; 6.0 Al; 5.0 Cr; 4.0 Tа; 1.6 Nb; 1.1 Mо; 0.16 С; 0.15 B; 0.025 Cе, 60.05 Ni. It further establishes the effect of the electrolyte’s composition on the indicators of electrochemical processing of the alloy in question: power yield, distribution of alloy components among the products of electrolysis, granulometric size of the anode slime. A quantitative separation of the ZhS32-VI alloy components occurs during its anode dissolution in acid electrolytes (the solution is a mixture of nitrogen and hydrochloric acid), conducted in a galvanostatic regime with a current power in the range from 1.0–2.5 A: refractory metals concentrate in anode slime: niobium, tantalum, molybdenum and tungsten, whilst cobalt, rhenium, aluminium, chrome and the basic quantity of nickel partially transfer into the electrolyte. Anode slime is an X-ray amorphous product in which refractory metals — niobium, tantalum, molybdenum and tungsten – concentrate during the processing. The chemical composition of anode slime does not change significantly in the case of the employed electrolytes, % (wt.): 4.8–3.2 Re; 2.5–4.9 Co; 28.4–32.6 W; 1.6–3.2 Al; 4.0–5.8 Cr; 13.2–14.5 Tа; 5.8–6.0 Nb; 3.2–4.8 Mо; 18.5–22.4 Ni. The sizes of anode slime particles depend on the composition of the employed electrolytes and range from 800 to 4500 nm. The cathode deposition, obtained during the research, consisted of nickel, cobalt, aluminium and rhenium. The yield of cathode sediments varies between 34.8% and 45.3%. The research showed that electrochemical processing, conducted in a galvanostatic regime by using acid electrolytes, enables the obtaining of a powdered nickel concentrate with the level of nickel no lower than 79.9% (wt.).

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