Electrochemical reduction mechanism of several oxides of refractory metals in FClNaKmelts

The dissolution characteristics and electrochemical reduction mechanism of oxides of refractory metals ZrO2, HfO2 and MoO3 in NaCl-KCl-NaF melts are studied. The results shows that there are no chemical reaction of ZrO2 and HfO2 in NaCl-KCl-NaF melts, the dissolution of MoO3 is chemically dissolved, and MoO3 reactwith melts to form Na2Mo2O7. The reduction process of zirconium in the NaCl-KCl-NaF-ZrO2 melts is a reversible process of one-step electron transfer controlled by diffusion. The electrochemical reduction process of ruthenium is a one-step reversible process and the product is insoluble; Electrochemical reduction of metallic molybdenum in melts is controlled by the diffusion and electron transfer process of active ion Mo2O3. The electrochemical reduction process of the metal molybdenum in the melts is carried out in two steps.