Ole Kleppa and coworkers have accurately measured the enthalpies of mixing
of a large number of binary molten salt systems. These results have also be
en proven to be useful in the analyses of phase diagrams and in creating a
reliable database on free energies of mixing of a large number of systems.
He made a general confirmation of a specific result by Hildebrand and Salst
rom that excess free energies of mixing of simple binary molten salts could
be represented by a simple polynomial. an important result for ionic syste
ms with very long range ionic pair interactions. His measurements of the en
thalpies of mixing of all binary alkali nitrates led to an expression which
was close to that deduced from a simple model by Forland. This result also
catalyzed the Conformal Ionic Solution Theory, the only theory fundamental
ly valid for molten salts. This theory later led to methods for accurately
predicting the solution properties of multicomponent molten salt systems fr
om data on the subsidiary binaries and the pure component salts. His measur
ements of binary systems with the two components having the same cation and
two different anions indicated that deviations from ideality were generall
y very small. A theoretical extension of this conclusion to silicates and o
ther polymeric slags led to reliable predictions of the solubilities (and s
ulfide capacities) of ionic compounds. Kleppa's work has had a major influe
nce on molten salt chemistry (C) 2001 Elsevier Science B.V. All rights rese
rved.