Irkutsk National Research Technical University, Irkutsk, Russia:

V. V. Elshin, Head of a Chair of Automation of Industrial Processes
A. P. Mironov, Assistant Professor of a Chair of General Education
A. E. Ovsyukov, Deanery Programmer, e-mail: a-ovsyukov@rambler.ru

Extraction of precious metals from ores is currently performed by using sorption technology. One of its important processes is desorption of metals from active coals. This article presents a mathematical model of kinetics of high-temperature desorption of gold from active coals, based on physicochemical principles of the process. The mathematical description takes into account the formation of an [AuCNOH]^– type intermediate at an intermediary stage of the desorption process, as well as decomposition of metallic gold which is not extracted during desorption. Identification of the model was carried out on the basis of experimental data on kinetics of the desorption process, which was presented through curves of relative values of desorption degrees as related to fictional lead times, depending on the experimental parameters. Numerical values of the model coefficients were obtained as a result of modelling. An adequacy analysis was performed on the obtained data based on the results of parallel experiments. The obtained analytical dependence of concentration changes of desorption products on the process parameters makes it widely usable in theoretical and practical calculations, as well as for designing a management system. Further research of the given process aims to study the basic principles of statics and dynamics of a high-temperature desorption of gold from active coals, and to optimize technological parameters for effective conduction of the process according to specific condition of gold mining companies.
This work was carried out with the financial support of the project No. 02.G25.31.0075 within the decree of the Government of the Russian Federation No. 218 on 09.04.2010.

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