The electrodeposition of scandium on a tungsten electrode was investigated in molten LiCl-KCl of eutectic composition at 673 to 823K by using cyclic voltammetry, chronopotentiometry and chronoamperometry. It was found that, during cathodic polarization, deposition of metallic Sc from the chloride mixture onto the tungsten surface proceeded in a single step, and that electrocrystallization played an important role in the process. Experimental current-time transients obeyed theoretical models based upon instantaneous nucleation, with 3-dimensional growth of nuclei. From chronopotentiometric measurements, the diffusion coefficient of Sc(III) ions was determined by applying the Sand equation and modifying the immersion depth of the working electrode in stages. The activation energy for diffusion was found to be 38.18kJ/mol, and the data could be described by: log[D(cm2/s)] = -2.48 – 1993/T. Electrochemistry of Scandium in the Eutectic LiCl-KCl. Y.Castrillejo, P.Hernández, J.A.Rodriguez, M.Vega, E.Barrado: Electrochimica Acta, 2012, 71, 166-72

Table 108

Diffusivity of Sn in LiCl-KCl Melts