A. A. Baikov Institute of Metallurgy and Material Science RAS, Moscow, Russia:

B. G. Balmaev, Leading Researcher, Laboratory of Physical Chemistry and Aluminum Technology, e-mail: 3.boris@gmail.com
A. S. Tuzhilin, Acting Leading Researcher, Laboratory of Physical Chemistry and Aluminum Technology, e-mail: dkdm@mail.ru
A. Yu. Shebalkova, Engineer of Laboratory of Physical Chemistry and Aluminum Technology

National University of Science and Technology “MISiS”, Moscow, Russia:

S. S. Kirov, Assistant Professor, Chair of Non-ferrous Metals and Gold, e-mail: kirovss@list.ru

This paper studied the process of interaction between the aluminum hydroxide and hydrochloric acid using probabilistic-determinative experiment planning. Probabilistic-determinative method of experiment planning based on a Latin square mean and Protodyakonov`s equation, takes into account the physical meaning of the dissolution process in private dependencies and adequately predict the process outside of the arguments measure. We investigated the effect of temperature and leaching duration, excess of aluminum hydroxide to stoichiometric formation of aluminum hydroxychloride Al(OH)Cl<sub>2</sub>. Experiments were performed in ampoule autoclaves. Stirring was performed by rotating the digesters themselves in a vertical plane. As a result of the approximation of the experimental data, we calculated the partial dependence of the atomic ratio of aluminum to chlorine in aluminum hydroxychloride at various factors. The greatest impact on the process of aluminium chlorohydrate production has a temperature of the process. Thus, at a temperature of 160 <sup>о</sup>C we obtained a mixture of aluminum chloride and aluminum hydroxychloride, and at 180 <sup>о</sup>C we obtained a product without aluminum chloride with atomic ratio of aluminum to chlorine of 0.5. By increasing the duration of the process from 3 to 5 hours, the atomic ratio of aluminum to chlorine varies from 0.41 to 0.5. The generalizing dependence for production process of aluminum hydroxychloride on the studied factors was determined by combining partial dependencies in Protodjakonov`s equation. To check the adequacy of given dependence, there was used a nonlinear coefficient of multiple correlation and its significance. The resulting mathematical model was used for optimization and forecasting process. Changing the initial conditions of aluminum hydroxide leaching process with hydrochloric acid according to the model, it is possible to predict the composition of obtained product in the field of values, where the experimental verification is non-value-added. Under optimal conditions, the interaction of aluminum hydroxide with hydrochloric acid in one step obtained low-basicity aluminium chlorohydrate (Al(OH)Cl₂) with atomic ratio Al:Cl = 0.504.
This work was carried out with the financial support of the Ministry of Education and Science of the Russian Federation within the subsidiary agreement on 02 November 2015, No. 14.581.21.0019 (unique identifier: RFMEFI58115X0019).

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