Electrochemical Studies of Chromium in Molten LiF ‐ NaF ‐ KF (FLINAK)

The mechanism of the reduction of Cr(III) in molten FLINAK was studied using cyclic voltammetry and chronopotentiometry over a temperature range of 612°–983°C and a Cr(III) concentration of 0.07 to 0.13 mol/l. Two reduction and two oxidation steps were observed, but extensive differences in the electrochemistry were seen over the measured temperature range. Cr(III) is reduced to Cr(II) followed by a two‐electron reduction of Cr(II) to Cr metal and both reduction processes are quasi‐reversible. The product of the first reduction process is soluble at 983°C, but is insoluble at lower temperatures.