The solid–liquid phase equilibria of the Li⁺, Na⁺, Ca²⁺//Cl^––H₂O quaternary system at 298.15 and 323.15 K are studied via the isothermal solubility phase equilibrium method. The solubility data and liquid properties of density and pH are obtained. The phase diagrams of the quaternary systems, including the water free diagram, the water diagram, and the dry salt diagram, are plotted to show the phase regions, water content, and salting-in effect. NaCl occupies the largest phase region at both 298.15 and 323.15 K. One double salt LiCl·CaCl₂·5H₂O occurs at 298.15 K and builds up two invariant points; one incommensurate invariant point saturated by (NaCl, LiCl·H₂O, LiCl·CaCl₂·5H₂O) and one commensurate invariant point saturated by (NaCl, CaCl₂·4H₂O, LiCl·CaCl₂·5H₂O), but at 323.15 K, no double salt forms. The salting-in effect that happened in ternary systems still occurs in the quaternary Li⁺, Na⁺, Ca²⁺// Cl^––H₂O system at both temperatures. NaCl saturated concentration increases with LiCl and CaCl₂ contents and results in a very high total salt content at commensurate invariant points, e.g., they are 56.92 and 60.62% at 298.15 and 323.15 K, respectively.

中文翻译：

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Li+、Na+、Ca2+//Cl––H2O 四元体系在 298.15 和 323.15 K 时的固液相平衡

采用等温溶解度相平衡法研究了Li ⁺、Na ⁺、Ca ²⁺ //Cl ^– –H ₂ O 四元体系在298.15和323.15 K下的固液相平衡。获得溶解度数据以及密度和pH 的液体特性。绘制四元体系的相图，包括无水图、水图和干盐图，以显示相区、含水量和盐析效应。NaCl在298.15和323.15 K处占据最大相区。在298.15 K处出现一种复盐LiCl·CaCl ₂ ·5H ₂ O，并建立两个不变点；1个被(NaCl, LiCl·H ₂ O, LiCl·CaCl ₂ ·5H ₂ O)饱和的无公度不变点和1个被(NaCl, CaCl ₂ ·4H ₂ O, LiCl·CaCl ₂ ·5H ₂ O)饱和的等量不变点，但在 323.15 K 时，没有复盐形成。在两种温度下，三元体系中发生的盐析效应在四元Li ⁺、Na ⁺、Ca ²⁺ // Cl ^– –H ₂ O体系中仍然存在。NaCl饱和浓度随着LiCl和CaCl ₂含量的增加而增加，并导致在相应的不变点处非常高的总盐含量，例如，在298.15 K和323.15 K处分别为56.92%和60.62%。