Thermodynamic treatment of multicomponent fused salt solutions: common anion reactive systems approximation

From a modified F.F.G. (1) thermodynamic cycle, equations have been developed from which the molar and partial molar excess thermodynamic properties of j-component molten salt solutions may be predicted from binary data.The theory is applicable to reactive molten salt systems and particularly to charge asymmetric fused salt solutions with common anions.It is shown that for a system having j + 1 components, such as [Formula: see text], any molar or partial molar property of mixing for MXq, may be calculated from available data on corresponding j-binary systems, such as MXq–AX, MXq–BX, and [Formula: see text].The equations are of the general form,[Formula: see text]The latter is applicable only when the multicomponent and the binary solutions have the same MXq content and same temperature.The theoretical expressions have been found to predict quite well available data on ternary and quarternary systems. New composition parameters for expressing the compositions in quarternary and quinary systems have been established. Key words: molten salt solutions, multicomponent systems, ternary systems, quarternary systems, quinary systems.

Thermodynamic properties of the dilute solutions of silver chloride and aluminum trichloride in alkali chlorides by electromotive force measurements

Thermodynamic data for dilute solutions of AgCl and AlCl3 in molten alkali chlorides were derived from the emf's of formation and of galvanic cells, respectively, given as, Ag/AgCl–ACl/C,Cl2 and Ag/AgCl–ACl//AlCl3–ACl/Al. ACl represents NaCl, KCl, CsCl, or the equimolar mixtures of NaCl–CsCl and KCl–CsCl. It was found that the thermodynamic properties of the ternary melts could be predicted from the results of the binary melts using the relationship (17, 20, 21), [Formula: see text] where Z represents any partial molar property. The ternary solution is denoted by the subscript 1, 2, 3 while the two binaries are denoted by 1, 2 and 1, 3; t is a concentration variable given as t = X3/(X2 + X3). These expressions are valid when the binary and the ternary solutions have the same content of either AgCl or AlCl3, respectively.