Addition Effect Of Fluoride Compounds For Zr Electrorefining In Licl-Kcl Molten Salts

The effect of fluoride compounds on Zr electrorefining is investigated for Zirlo cladding tubes in LiCl-KCl based molten salts. Cyclic voltammetric curves exhibit a modification of electrochemical behaviors of Zr ions from a two-step reduction process in LiCl-KCl-0.07 M ZrCl4 salts to one-step reduction by the addition of 0.84 M LiF. Morphological features of Zr deposits are found to also be changed from a powder type to a dendritic characteristic, thereby reducing the amount of incorporated salts and enhancing the crystallinity of electrorefined Zr. Quantitative measurement reveals that the Zr content in the deposit is increased by the addition of fluoride compounds, which is expected to enhance the recovery yield of Zr.