Thermodynamic modeling and phase diagram prediction of salt lake brine systems Ⅱ.Aqueous Li+-Na+-K+-SO4-and its subsystems

• 作者: Huan Zhou Peng Wu Wenxuan Li Xingfan Wang Kuo Zhou Qing Hao
• 来源期刊: 中国化学工程学报（英文版）
• 年，卷（期）: 2021,（6）
• 所属期刊栏目: Chemical Engineering Thermodynamics
• 页码范围: 134-149
• 页数: 16页
• 语种: 英文

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,multi-temperature and high concentration.The essential subsystem of sulfate type brine,aqueous Li+-Na+-K+-SO42-and its subsystems across a temperature range from 250 K to 643 K are investigated with the improved comprehensive thermodynamic model.Liquid parameters(ΔgIJ,ΔhIJ,and ΔCp,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 ΔfGk°(298.15)and ΔfHk°(298.15)of 11 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 Li2SO4-Na2SO4-H2O,Li2SO4-K2SO4-H2O and Na2SO4-K2SO4-H2O ternary systems.The predicted results of com-plete structure and polythermal phase diagram of ternary systems and the isothermal phase diagrams of quaternary system excellently match with the experimental data.