Solubility of oxides in the KBr-BaBr2 eutectic melt (0.495: 0.505) at 973 K

Solubility products of MnO (pK _s,MnO = 6.32 ± 0.1), NiO (pK _s,NiO = 8.06 ± 0.2), and PbO (pK _s,PbO = 4.04 ± 0.2) in KBr-BaBr₂ (0.495: 0.505) melt at 973 K were determined by potentiometric titration using a Pt(O₂)|ZrO₂(Y₂O₃) membrane oxygen electrode. A significant increase in oxide solubilities compared to those of 2CsBr · KBr melt is attributed to the enhancement of acidic properties of cations in the series Cs⁺, K⁺-Ba²⁺, ensuring a greater degree of binding of oxide ions that results from dissociation of the oxide under study to the cationic framework of the melt. The solubilities of the investigated oxides in chloride and bromide melts with similar cationic compositions are virtually identical.