The solubility of MgF2, CaF2 and ZnF2 in aqueous solution is seldom studied. Their solubility data available in literature conflict with each other and their change tendency with temperature is hard to draw. In this work we elaborately measured their solubility over the temperature range from 298.15 K to 353.15 K. To guarantee the data reliability, various methods include EDTA-titration and FISE have been used for the ion content analysis in the saturated solutions and the X-ray diffraction (XRD) for the equilibrium solid phase identification. Besides, sufficient solid-liquid contact time has been taken to guarantee the equilibrium. The determined results were compared with those reported in literature and their differences have been discussed. It was found that the MgF2 solubility decreases, however, the CaF2 solubility increases with increasing temperature. In the ZnF2+H2O system the equilibrium solid phase is ZnF2*4H2O(s) at temperature below 333 K and ZnOHF(s) above 333 K. While the ZnF2*4H2O(s) solubility is sensitive to temperature, the ZnOHF(s) solubility is insensitive.
Compounds
#
Formula
Name
1
F2Mg
magnesium difluoride
2
CaF2
calcium fluoride
3
F2Zn
zinc fluoride
4
H2O
water
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.