ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Chronopotentiometnc study of the molten system NaCI—KCl—AICI₃

P. Fellner, Ž. Lubyová, and M. Gabčo

Institute of Inorganic Chemistry, Centre of Chemical Research, Slovak Academy of Sciences, CS-842 36 Bratislava

Abstract: The cathodic process in the NaCl-KCl-AlCl₃ melt, was studied by the chronopotentiometric method. The kinetics of the process are controlled mainly by diffusion. The electrochem. reaction is, however, preceded, by a chem. reaction. It is suggested that this reaction corresponds to the decompn., of the complex ion, AlCl₄. Since the KAlCl₄ is more stable than NaAlCl4 its suggested that kinetics of the process are controlled by the chem. reaction KAlCl₄ ↹ AlCl₃ + KCl. At the temp. T = 1000 K, D = (5.5 ± 0.5) × 10^-5 cm² s^-1. After depletion of the electroactive species which is formed by, the chem. reaction, the direct redn. of Al from the complex AlCl₄^- starts. This process proceeds at the potential ∼130 mV more neg. compared to that of redn. of Al from AlCl₃.

Full paper in Portable Document Format: 375a617.pdf

Chemical Papers 37 (5) 617–622 (1983)