New electrochemical measurements of the liquidus in the lithium fluoride-beryllium fluoride system. Congruency of lithium beryllium fluoride (Li2BeF4)

Thermodynamic evaluation of the (LiF+NaF+BeF2+PuF3) system: An actinide burner fuel

“…In order to obtain a correct shape of the liquidus line it was necessary to optimize the excess entropy terms of the excess Gibbs free energy function of the liquid solution as well as the D f H (298.15) and S (298.15) parameters of the LiBeF 3 15), and C p data for the gaseous species. agreement with the experimental points [19][20][21]. A comparison between the calculated mixing enthalpies and the measured values [18] is indicated in figure 2 and again a very good correlation has been achieved.…”

A miscibility gap in LiF–BeF2 and LiF–BeF2–ThF4

“…d Obtained by optimization. [4]; (h) data by Thoma et al [6] and (4) data by Romberger et al [7]. [19].…”

“…At the time this ternary diagram was investigated experimentally, there were uncertainties whether the compound 2LiF AE BeF 2 melts incongruently or not. Detailed measurements by Romberger et al [7] revealed that it is a congruently melting compound, so that the first two invariant points by Thoma et al could therefore be interpreted as eutectic instead of peritectic.…”

“…For this method, liquidus data and extrapolated data on isothermal activity coefficients were needed, which were provided by several phase diagram measurements [6,7] and an electromotive force study [15]. The result was a two-liquid region, which is almost entirely below the liquidus, i.e.…”

“…For these reasons, the LiF-BeF 2 phase diagram has been investigated by several researchers, for example Thilo and Lehmann [1], Roy et al [3,4], Novoselova et al [5], Thoma et al [6] and Romberger et al [7]. However, disagreements exist between the results, especially on the BeF 2 -rich side, probably because of the experimental difficulties to perform measurements on the highly viscous melt.…”