A Partial Phase Study o the System NaF–HF

Elimination of AsF3 from anhydrous HF using AgFAsF6 as a mediator

“…Most of the resulting HF was distilled onto $4 mL of frozen H 2 O in another PFA reactor to give Sample F-2. Complete transfer of HF was difficult at this stage, due to the strong HF-absorption ability of NaF (forming Na(FH) n F [14,15]). Sample F- 1 provided the As content of the original HF, and Sample F-2 provided that of the HF treated with F 2 as shown in Table 1.…”

Thermal properties of hydrofluorides

“…Table 6 Enthalpies of ammonium hydrofluoride decomposition processes d. Thermal Anal. 6,1974 Measurements of the vapour pressure above NH4F" 3HF have given the relationship [11 ] Prom = -5288/T + 20.97 (263-296.4~…”

“…Later, more exact data for alkali metal and ammonium hydrofluorides were obtained by studying the melt diagrams of the systems HF -MF [6][7][8][9][10][11]. Experimental data indicate that of the above hydrofluorides only NaF.…”

“…The temperature at which decomposition is completed increases from potassium to caesium [28]. 6,1974 The vapour pressure of HF above KF 9 HF has been measured in the temperature range 230.5-347.5 ~ [30]. The temperature dependence of the vapour pressure of HF above/~-phase KF " HF is given by the equation log Prom = 8.57-4000/T (196-238.7 ~…”

Les systemes binaires fluorure de lithium-fluorure d'hydrogene et fluorure de sodium-fluorure d'hydrogene

“…Les diagrammes LiF-HF et NaF-HF ont 6t6 6tablis dans le but de compl6ter les donn6es bibliographiques. Les r6sultats concernant le syst~me LiF-HF sont tr6s fragmentaires; le binaire NaF-HF a 6t6 6tabli, dans un domaine limit6 de concentration, successivement par Euler [2] et par Adamczack, Mattern et Tieckelman [3] mais les conclusions de ces travaux sont contradictoires.…”