The Electroreduction of Gadolinium and Dysprosium Ions in Equimolar NaCl-KCl Melt

Hasbi B. Kushkhov, Aziza S. Uzdenova, Mahmoud M. A. Saleh, Abdalkader M. F. Qahtan, Lily A. Uzdenova

Kabardino-Balkarian State University, Nalchik, Russia.

DOI: 10.4236/ajac.2013.46A006                

Abstract

The mechanism of rare earth metals (Gd and Dy) chloride complexes electroreduction on the tungsten electrode in equimolar NaCl-KCl melt at 973 K has been studied by linear and cyclic voltammetry. Some kinetic parameters of processes were calculated. It was shown that the tungsten electrode was indifferent to gadolinium and dysprosium which were reduced on the surface. We found that the discharge mechanism of gadolinium and dysprosium chloride complexes was described by three-electron step when the steady-state conditions of polarization were limited by the mass transfer stage. The conditions of nonstationary polarization made the slowness of the charge transfer stage. The diffusion coefficient of gadolinium and dysprosium ions was calculated, the diffusion coefficient of GdCl^3-₆ ions was (0.9 ± 0.2) × 10^-5 cm^2.s^-1, and for DYCI^3-₆ ions, it was (1.60 ± 0.2) × 10^-5 сm^2.s^-1.

Keywords

Molten Chlorides; Gadolinium Trichloride; Dysprosium Trichloride; The Electroreduction Mechanism; Tungsten Electrode; Linear and Cyclic Voltammetry; The Diffusion Coefficient

Conflicts of Interest

The authors declare no conflicts of interest.

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