Thermodynamics of Simple Molten Salt Mixtures

  • O. J. Kleppa
Part of the Advances in Physical Geochemistry book series (PHYSICAL GEOCHE, volume 1)


During the past 30 years there has been an enormous increase in our knowledge and understanding of molten salt mixtures. In earlier years thermodynamic work in this area was based exclusively on equilibrium measurements, i.e., on applications of chemical equilibrium, emf, vapor pressure, and/or cryoscopic methods of investigation. During the last two decades new insight has been gained also from calorimetric studies, particularly from measurements of the enthalpies of mixing. On the whole we now find that the most reliable thermodynamic information for such systems consist of the Gibbs energies from equilibrium work, enthalpies from calorimetry, and entropies from a combination of these two methods. For theoretical and other background information the reader is referred to a 1976 review of the thermodynamics of molten salt solutions prepared for the NATO Advanced Study Institute “Thermodynamics in Geology” (Kleppa, 1977). The present paper summarizes experimental developments since that time.


Potassium Fluoride Aluminum Fluoride Common Anion NATO Advance Study Institute Excess Chemical Potential 
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© Springer-Verlag New York Inc 1981

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  • O. J. Kleppa

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