Electrode reaction of Pr on Sn electrode and its electrochemical recovery from LiCl-KCl molten salt

Summary To recover Pr from molten chlorides, the electrode reactions of Pr 3+ on Sn-coated W and liquid Sn electrodes were studied by a group of electrochemical techniques. CV and SWV results exhibited that the electrochemical signals pertaining to the formation of Pr-Sn alloy compounds and solid solution appeared at less negative potentials than that of Pr 3+ on W electrode. The thermodynamic data of Pr-Sn alloy compounds and the kinetic parameters for PrSn 3 /Pr 3+ pair were determined employing OCP, LP, and Tafel methods, separately. The measured diffusion coefficient ( D ) of Pr in liquid Sn metal was 9.40 × 10 −6 cm 2 s −1 . Furthermore, the electrochemical recovering Pr from molten salt was performed using liquid Sn as a working electrode, and the formed Pr-Sn samples characterized by XRD and SEM-EDS were composed of Sn and PrSn 3 phases.