Kazan National Research Technological University, Kazan, Russia:

A. U. Aetov, Master’s Student at the Department of Heat Engineering Fundamentals, e-mail: aetovalmaz@mail.ru
R. A. Usmanov, Professor at the Department of Heat Engineering Fundamentals, Doctor of Technical Sciences, e-mail: usmanoff@gmail.com
S. V. Mazanov, Associate Professor at the Department of Heat Engineering Fundamentals, Сandidate of Technical Sciences, e-mail: serg989@yandex.ru
F. M. Gumerov, Professor, Head of the Department of Heat Engineering Fundamentals, Doctor of Technical Sciences, e-mail: gum@kstu.ru

One of the promising ways to solve the environmental problems are associated with the disposal of industrial waste as well as isolating molybdenum and important organic components from the wastewater. There could be used processes with working environments in a supercritical fluid (SCF) state which studied in this article. This approach was the subject of research the results of which are presented in the work. Previously the authors of the article opted for combining a supercritical fluid extraction process with carbon dioxide as an extracting agent. Since the task was to isolate organic compounds and oxidize the remaining organic components of wastewater and simultaneously precipitate the inorganic component under supercritical conditions for an aqueous solution. Both processes turned out to be knowledge-intensive and saturated. The implementation of the oxidation process in supercritical conditions has significant advantages over traditional methods, namely, thermal neutralization and control disposal by reducing the amount of emissions into the atmosphere and soil, improving the quality of neutralization, and the possibility of recycling neutralized water. It is possible to use the heat of an exothermic reaction for internal production needs with the appropriate composition of the wastewater. The article presents the results of a study of the oxidation process of an industrial molybdenum-containing wastewater of a propylene epoxidation process carried out under supercritical fluid conditions (T = 673–873 K, P = 22.5 MPa). The experiments were carried out in a flow reactor using oxygen from air as an oxidizing agent. It was studied the influence of thermodynamic conditions on the efficiency of the process of oxidation of organic compounds of wastewater. There was isolated and characterized the elemental composition of the inorganic residue in which the concentration of molybdenum was carried out on the plant of a highfrequency induction plasma.
The authors would like to thank the Russian Foundation for Basic Research (Agreement No. 18-29-06041) for the funding provided to them.

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