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Journal of Applied Electrochemistry

, Volume 12, Issue 5, pp 545–548 | Cite as

Decomposition voltage for the electrolysis of alumina at low temperatures

  • R. C. Dorward
Papers

Abstract

The apparent decomposition voltage for the electrolysis of alumina in an equimolar Na3AlF6-Li3AlF6 electrolyte was measured over a temperature range of 800 to 1000° C by the extrapolation of voltagecurrent plots to zero current. Temperature coefficients of −1.9 and −2.4 mV° C−1 were determined for conditions of variable alumina activity (constant concentration) and unit activity (saturated), respectively. The overvoltage contribution to the temperature dependency was estimated to be about −1.6mV° C−1 (versus a −0.6 mV° C−1 dependency for the reversible decomposition voltage). Reduced alumina solubility at low temperatures also appeared to increase the overvoltage, but was of secondary importance.

Keywords

Alumina Physical Chemistry Temperature Coefficient Unit Activity Constant Concentration 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Chapman and Hall Ltd. 1982

Authors and Affiliations

  • R. C. Dorward
    • 1
  1. 1.Center for TechnologyKaiser Aluminum & Chemical CorporationPleasantonUSA

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