The nature of IIa Oxides in cryolite melts: On the system of cryolite-MgO, -CaO, and -BaO

Abstract

The nature of IIa Oxides, particularly MgO, CaO and BaO, in cryolite melts was studied by means of the freezing point depression of cryolite. In the binary system of these melts, the displacement reaction accompanied and the formation of fluorides and aluminate were observed by the X-ray diffraction analysis.
As the mechanism of the reaction, it is the most probable that the formation of complex ions of Al₂O₃^- and MgF₃^- occures in the system of cryorite-MgO, while the formation of AlO₂^- and the dilution of Na⁺ by Ca²⁺ or Ba²⁺ are almost identical in the system of cryolite -CaO, and -BaO.