The electrochemical behavior of dissolved Fe2O2 in 82.5CaCl2-17.5KF (mole percent, %) was studied using cy clic voltammetry, chronoamperometry, and galvanostatic electrolysis at 827 ℃, and the deposits were characterized by XRD and SEM. Pure iron was deposited on a rotating cylinder (210 r/min) with a cell voltage less than -- 1.0 V. Deposition rate was controlled by diffusion on a molybdenum electrode. The diffusion coefficient of iron species Fe( Ⅲ ) in the melt at 827 ℃ was found to be 9.7×10^-5 cm^2/s.
The cathodic behavior of molten CaCl2, CaCl2-CaO and equimolar CaCl2-NaCl-CaO was studied by cyclic voltammograms and constant potential polarization at temperatures of 1123 to 1173 K on molybdenum and titanium electrodes. The diffusion coefficient of Ca2+ (CaO) in molten CaCl2-CaO was calculated from the linear relationship between the square root of scan rate and the peak current density. The deposition potentials and the potential temperature coefficient of CaO in molten CaCl2-0.5mol%CaO and CaCl2-NaCl-0.5mol%CaO were also obtained from their cyclic voltammograms. The result shows that CaO is more easily reduced than CaCl2. The addition of NaCl in molten CaCl2-CaO induces the underpotential electrodeposition of CaO.