Vol. 337 No. 6 (2026)
DOI https://doi.org/10.18799/24131830/2026/6/5449
Forecasting operating modes of large-scale electrochemical apparatus for fluorine production
Relevance. Fluorine is produced industrially by electrolytic decomposition of hydrogen fluoride from a melt of potassium hydrofluoride (trifluoride) KF 2HF, mainly by the so-called medium-temperature method at temperatures from 80 to 115°C. In apparatuses (electrolyzers) having the shape of a rectangular parallelepiped, the main structural elements are a steel body and a louvered cathode, a carbon (coke) anode, a bell, electrolyte heating and cooling systems, as well as monitoring and control systems. Aims. An experimental study of the impact of electrolysis voltage, electrolyte temperature, and hydrogen fluoride concentration in the electrolyte on the anode current density, anode gas yield, and fluorine content in the anode gas during the electrolytic production of fluorine in a pilot electrolyzer. Derivation of a multiple regression equation based on the dependence of the anode current density on the previously specified process parameters for a pilot electrolyzer and its comparison with a similar equation obtained earlier for a laboratory electrolyzer. Methods. Experimental and theoretical studies, physicochemical and chemical methods of analysis. Object. Laboratory and pilot plant for medium-temperature fluorine production. Results. The authors have studied the effect of the electrolysis voltage (U) from 5 to 15 V, electrolyte temperature from 80 to 120°C, hydrogen fluoride concentration from 37.0 to 41.5 wt % on the anode current density (i, A/cm2) in a pilot electrolyzer. It was established that the anode current density grows proportionally to the increase in electrolysis voltage, while the yield of the anode gas grows and the fluorine content in it increases; with an increase in the process temperature, the electrolysis voltage decreases, which leads to growth in the amount of the released anode gas and the fluorine content in the anode gas; with an increase in the HF content in the electrolyte, the voltage of the electrolysis decreases and the amount of the released anode gas grows. By processing experimental data obtained in a pilot electrolyzer, a multiple regression equation was derived for the dependence of anode current density on voltage, temperature, and hydrogen fluoride concentration. The multiple regression equations obtained in the laboratory and pilot electrolyzer studies are similar, and the second equation can be derived from the first by multiplying by an adaptation coefficient of 0.182. Thus, the results of the laboratory studies allow us to predict the performance of pilot and industrial electrolyzers.
For citation: Sofronov V.L., Tkachuk S.A. Forecasting operating modes of large-scale electrochemical apparatus for fluorine production. Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2026, vol. 337, no. 6, pp. 65-73. https://doi.org/10.18799/24131830/2026/6/5449
Keywords:
fluorine, medium-temperature electrolysis, laboratory and pilot electrolyzers, anode current density, voltage, temperature, hydrogen fluoride concentration, regression equations, adaptation coefficient
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