文摘
Solubility isotherms of the ternary Ca(NO3)2–LiNO3–H2O system were elaborately determined at T = (273.15, 298.15, and 323.15 K) by an isothermal equilibrium method, and the results showed that there are two stable solubility branches for the solid phases Ca(NO3)2·4H2O and LiNO3·3H2O at 273.15 K, and four stable solubility isotherms for the solid phases Ca(NO3)2·4H2O, Ca(NO3)2·3H2O, LiNO3·3H2O, and LiNO3 at 298.15 K, and solubility data corresponding to solid phases Ca(NO3)2·3H2O, Ca(NO3)2·2H2O, and LiNO3 at 323.15 K. The experimental data were correlated by a modified Brunauer–Emmett–Teller (BET) model to obtain the complete phase diagram of the ternary system over the temperature range from 273 to 373 K. On the basis of the simulated polytherms, an eutectic point Ca(NO3)2·4H2O + LiNO3·3H2O was recognized, and the melting temperature and fusion heat are 290.5 K and 139.8 J·g–1, respectively, measured by differential scanning calorimetry.