Regularities of cathode deposit formation during simultaneous reduction and exchange reactions. The mechanism of UO2–ZrO2 cathode deposit formation

Highlights: •The paper describes an empirically demonstrated mechanism of cathode UO2–ZrO2 deposit formation during the (NaCl–KCl)equim.−UO2Cl2–ZrCl4 melts electrolysis. •The deposits are formed at simultaneous reduction and exchange reactions. •The paper provides equations for the UO2–ZrO2 formation. -- Abstract: This paper describes an empirically demonstrated mechanism of UO2–ZrO2 cathode deposit formation during the (NaCl–KCl)equim.–UO2Cl2–ZrCl4 melts electrolysis. The first layer of the cathode product was formed through UO22+ ion reduction to uranium dioxide followed by an exchange reaction with Zr4+ ions, which are present in the electrolyte. The subsequent reactions proceeded through simultaneous reduction and exchange reactions at the cathode