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

ABSTRACT

The phase equilibria relationship of quaternary system LiCl-KCl- Li2SO4-K2SO4-H2O and its subsystem LiCl-KCl-H2O and LiCl-Li2SO4-H2O were studied by the isothermal dissolution equilibrium method at 288.15 K and the corresponding phase diagrams were drawn. At 288.15 K, ternary systems LiCl- KCl-H2O and LiCl-Li2SO4-H2O all belongs to a simple type. In the phase diagram of quaternary system LiCl-KCl-Li2SO4-K2SO4-H2O, there are five equilibrium solid phase crystallization fields: LiCl*2H2O, KCl, Li2SO4*H2O, K2SO4 and Li2SO4*K2SO4. Compared with the multi-temperature phase diagrams of this system at 288.15 K-348.15 K, it was found that the basic configuration of the phase diagrams is the same. As the temperature increased, the phase region of double salt Li2SO4*K2SO4 clearly increased, while the phase region of single salt KCl and K2SO4 clearly decreased. On the basis of the experiment, the extended Harvie-Weare (H-W) model of the Pitzer model was used to predict the solubility data of the quaternary system. The simulated and measured values were basically agreement.