Liquidus temperatures and phase equilibria in the BaCl2–MCl–BaO systems

Abstract

The liquidus temperatures of the BaO–BaCl₂–MCl systems (with M = alkali metal) are determined by thermal analysis. The caloric effects observed during melting of the barium-containing chloride eutectic with barium oxide additions are studied. A chemical mechanism of barium oxide dissolution in the melts is confirmed. X-ray diffraction patterns taken for the melt solidified after experiment indicate the presence of barium oxychloride Ba₄OCl₆ in the solid phase. It is shown that the significant increase in the liquidus temperature in adding the barium oxide to barium-containing chloride molten mixtures is related to substantial changes in their composition and structure.