Calorimetric and thermal analysis investigations of the MF-LaF3 mixtures (M equals alkali metal)

A systematic thermodynamic investigation of the LiF-LaF3, NaF-LaF3, KF-LaF3, RbF-LaF3 and CsF-LaF3 molten salt systems is reported in the present work, Enthalpy of mixing was measured by direct high temperature calorimetry at temperatures ranging 1046-1183 K. Equilibrium phase diagrams were determined by Differential Scanning Calorimetry (DSC). The same DSC technique was also used to measure the heat capacity, the enthalpies of transition and of fusion for the RbLaF4 and Cs3LaF6 stoichiometric compounds and for some NaF-LaF3 mixtures, Finally, interactions in the melts were discussed in terms of the Hoch-Arpshofen model.