Institute of Metallurgy, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia

D. S. Reutov, Junior Researcher, e-mail: reutov-ds@mail.ru
B. D. Khalezov, Chief Researcher
L. A. Ovchinnikova, Senior Researcher
A. S. Gavrilov, Junior Researcher

Flotation processing of copper-smelting dump slags expedites accumulation of floatation tails. According to chemical analysis results, these tails contain about 0.5% (mass) of copper and 4% (mass) of zinc. Copper and zinc are both included into primary and secondary mineral compounds as isomorphous impurities, and form their own mineral phases, including copper (0.76% mass) and zinc (9.24 % mass) ferrites. To develop technology for extraction of copper and zinc from tailings, it is necessary to determine the direction of research. To this end, copper ferrite was synthesized according to the ceramic technology, which consists in the joint thorough grinding of the stoichiometric amount of copper and iron oxides, followed by sintering in a muffle furnace at T = 1000–1100 ^оC and holding for at least 12 hours. From synthesized ferrites were compressed tablets on a hydraulic press under a load of 40 MPa. Tablets of 20 mm size were pasted into the holder of PTFE using epoxy glue. An experimental study was made of the rate of dissolution of copper ferrite by the rotating disc method. A laboratory setup was used, which consists of a water bath, a stirring device with speed control, a thermometer and a pH meter. Kinetics of copper ferrite (CuFe₂O₄) dissolution in aqueous solution of sulfuric acid were examined under different concentrations, temperature, and hydrodynamical regime. Established dissolving copper ferrite mode. According to the Arrhenius equation, the value of the experimental (apparent) activation energy of the process. The experimental rate constant is calculated. A conclusion is drawn on the kinetic mode of dissolution of CuFe₂O₄. The data obtained are the basis for the technology being developed.

The study was conducted in the framework of the State order of the Russian Academy of Sciences No. 0396-2017-0002.

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