Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

Solid-liquid phase equilibrium of the two ternary systems (Li2B4O7 + MgB4O7 + H2O) and (Na2B4O7 + MgB4O7 + H2O) at T = 298.15 K and p = 0.1MPa were studied with the isothermal dissolution equilibrium method. Solubilities and physicochemical properties including density, refractive index and pH value were measured experimentally. In the ternary system (Li2B4O7 + MgB4O7 + H2O) at 298.15 K, there are one invariant points corresponding to (Li2B4O7*3H2O + MgB4O7*9H2O); two isothermal dissolution curves; and two crystallization regions. The crystallized area of MgB4O7*9H2O is increased obviously with the increasing of temperature, while that of Li2B4O7*3H2O is decrease slightly. In the ternary system (Na2B4O7 + MgB4O7 + H2O) at 298.15 K, there are one invariant point (Na2B4O7*10H2O + MgB4O7*9H2O), two isothermal dissolution curves, and two crystallization regions. The crystallized area of MgB4O7*9H2O is increased with the increasing of temperature, while that of Na2B4O7*10H2O is decrease obviously. Both of systems belong to a simple eutectic type, and neither double salts nor solid solutions formed.