Abstract
Visual observations of several molten salt electrolysis processes were made in a two-compartment, see-through quartz cell. The electrolyses of aluminium, magnesium, lead, zinc, sodium and potassium were studied. The colour of the melt in the anode compartment was pale yellow for fluoride-chloride melts and red for chloride melts, caused by the presence of dispersed anode gases during electrolysis. In the cathode compartment, streamers of metal fog were formed. The colours of the metal fog were purple for aluminium, grey for magnesium, lead and zinc, blue for sodium and green for potassium.
The metal fog tended to sink to the bottom of the cell, which indicated that it had a higher density than that of the melt. The metal fog also penetrated into the anode compartment, probable due to convection and diffusion in the melt. The most probable explanation of the nature of the metal fog is that it consisted ofdispersed metal particles. This chemically unstable phase dissolved easily in the melt and was oxidized quickly by the anode gases.
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References
K. Grjotheim, C. Krohn, M. Malinovsky, K. Matiasovsky and J. Thonstad, ‘Aluminium Electrolysis — Fundamentals of the Hall-Héroult Process’, 2nd edn, Aluminium-Verlag, Düsseldorf (1982) pp. 293–318.
W. E. Haupin and W. C. McGrew, in ‘Light Metals 1974’, Proceedings, 103rd AIME Annual Meeting, Vol. 1, p. 37.
Qiu Zhuxian, Fan Liman and K. Grjotheim, in ‘Light Metals 1986’, Proceedings, 115th AIME Annual Meeting, p. 525.
Qiu Zhuxian, Fan Liman, Feng Naixiang, K. Grjotheim and H. Kvande, in ‘Light Metals 1987’ Proceedings, 116th AIME Annual Meeting, p. 409.
R. E. Andresen, Dr.ing. thesis, University of Trondheim, Norway (1978).
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Zhuxian, Q., Liman, F., Grjotheim, K. et al. Formation of metal fog during molten salt electrolysis observed in a see-through cell. J Appl Electrochem 17, 707–714 (1987). https://doi.org/10.1007/BF01007805
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DOI: https://doi.org/10.1007/BF01007805