Omsk State Pedagogical University (Omsk, Russia):
I. V. Skvortsova, Cand. Chem., Associate Prof., Dept. of Chemistry, e-mail: i_dorovskih@mail.ru

Bauman Moscow State Technical University (Moscow, Russia):
E. A. Eliseeva, Cand. Chem., Associate Prof., Dept. of Chemistry, e-mail: yakusheva@bmstu.ru
A. I. Karnyushkin, Cand. Chem., Associate Prof., Dept. of Chemistry, e- mail: him_expert@mail.ru
V. S. Boldyrev, Cand. Eng., Associate Prof., Leading Engineer of the Automation and Robotics Engineering
Center, e-mail: boldyrev.v.s@bmstu.ru

Chrome is part of many alloyed steels and wear-resistant composite electrochemical coatings. Chromium films are used as firming coatings of metal products and cutting tools in electronic technology. Chromium alloys are used in industry for the manufacture of parts of machines and mechanisms intended for operation in extreme conditions for the formation of durable coatings on metal and other surfaces. Therefore, the question of optimizing the technologies of etching, leaching and enrichment of chromium-containing ores. The paper discusses the kinetic features of the dissolution of chromium hydroxide (III) and proposes the optimal mechanism for the dissolution of chromium hydroxide (III) α-CrOOH in the presence of various ions (sulfate and nitrate) in acidic environments. The influence of various mineral acid ions on the kinetics of dissolution of chromium hydroxide (III) α-CrOOH in acidic environments is considered. The mechanism of dissolution of chromium hydroxide (III) α-CrOOH is proposed from the standpoint of various model representations. The most important direction of research in metallurgy is the selection of effective reagents and determining the main kinetic parameters of dissolution processes. An analysis of data on the influence of the nature of mineral acids on the rate of dissolution of chromium hydroxide (III) α-CrOOH is carried out. To calculate the empirical values of kinetic parameters, the methods of regression analysis were used. In order to select the technological regimes of the selective extraction of valuable metals from raw materials, the following parameters are considered (with acid and anions, T, pH).

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