| 摘 要： | It is still a challenging task to accurately and temperature-continuously express the thermodynamic properties and phase equilibrium behaviors of the salt-lake brine with multi-component,multitemperature and high concentration.The essential subsystem of sulfate type brine,aqueous Li~+-Na~+-K~'-SO_4~(2-) and its subsystems across a temperature range from 250 K to 643 K are investigated with the improved comprehensive thermodynamic model.Liquid parameters(Δg_(IJ),Δh_(IJ),and ΔC_(p,IJ)) associated with the contributions of Gibbs energy,enthalpy,and heat capacity to the binary interaction parameters,i.e.the temperature coefficients of eNRTL parameters formulated with a Gibbs Helmholtz expression,are determined via multi-objective optimization method.The solid constants Δ_fG_k°~((298.15)) and Δ_fH_k°~((298.15)) of11 solid species occurred in the quaternary system are rebuilt from multi-temperature solubilities.The modeling results show the accurate representation of(1) solution properties and binary phase diagram at temperature ranges from eutectic points to 643 K;(2) isothermal phase diagrams for Li_2SO_4-Na_2SO_4-H_2O,Li_2SO_4-K_2SO_4-H_2O and Na_2SO_4-K_2SO_4-H_2O ternary systems.The predicted results of complete structure and polythermal phase diagram of ternary systems and the isothermal phase diagrams of quaternary system excellently match with the experimental data.
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