V. E. Krotov, E. S. Filatov.
ABSTRACT
A mathematical model is presented for the electrolytic synthesis of a crystalline cathode deposit UO2-ZrO2 with simultaneous and continuous electrochemical and chemical reactions occurring on the electrode. Uranium dioxide is formed by an electrochemical reaction during the reduction of uranyl ions UO22+, zirconium is emerges by a chemical exchange reaction. Using the Faraday and Fick’s equations, an expression was obtained for calculating the content of zirconium dioxide in the UO2-ZrO2 system, which adequately describes the process of its synthesis in the NaCl-KCl-UO2Cl2-ZrCl4 melt. Qualitative coincidence of the geometric shape of the dependences, and, in some cases, quantitative correspondence of the calculated and experimental values of the zirconium dioxide concentration on the process conditions (ZrCl4 concentration, current density and duration of electrolysis, temperature) was established. The discrepancy between the values is explained by the volatilization of a part of ZrCl4 from the electrolyte during electrolysis, which was not taken into account when deriving the analytical equation.
KEY WORDS: salt melt, electrochemical and chemical reactions, mathematical model, cathode deposit, UO2-ZrO2, analytical equation, ZrO2 content.
DOI: 10.31857/S0235010623050067
EDN: ZQZOKN