采用等温溶解平衡法研究了四元交互体系Li^+,K^+//Cl^-,B4O7^2--H2O 323K时的相关系。该四元交互体系323K下的溶解度等温图含有4个盐类结晶相区、5条单变量线和2个无变量点。4个结晶相区分别对应于盐LiCl·H2O、KCl、Li2B4O7·3H2O和K2B4O7·4H2O的结晶区。2个无变量点标注为E和F。E点平衡固相为LiCl·H2O+KCl+Li2B4O7·3H2O,对应的平衡液相组成为w(Li^+)6.55%,w(K^+)2.16%,w(Cl^-)34.57%,w(B4O7^2-)1.89%;F点平衡固相为KCl+Li2B4O7·3H2O+K2B4O7·4H2O,对应的平衡液组成为w(Li^+)2.35%,w(K^+)2.37%,w(Cl^-)12.08%,w(B4O7^2-)4.56%。研究结果表明,该四元交互体系为简单共饱和型,体系中没有复盐和固溶体的形成。
The equilibrium solubility of the reciprocal system Li^+ , K^+//Cl^- , B4O7^2- -H2O at 323 K was studied by isothermal dissolution equilibrium method. Based on the solubility data, the phase diagram was plotted, in which there are four crystallization fields, five univariant curves and two invariant points. At the invariant point E, the saturated solid salts are LiCl· H2O, KCl and LiEB4O7 · 3H2O, and the corresponding composition of its equilibrium solution is w(Li^+ ) 6.55%, w(K^+ ) 2.16%, w( Cl^- ) 34.57%, w ( B4O7^2- ) 1.89%. The saturated solid salts of invariant point F are KCl, Li2B4O7 · 3H2O and K2B4O7 · 4H2O, and the corresponding composition is w (Li^+ ) 2.35%, w (K^+ ) 2.37%, w (Cl^-) 12.08%, w (B4O7^2- ) 4.56%. The experimental result shows that this system is of eutectic type, no complex salt or solid solution is formed.