三元体系Li^(+)(K^(+)),Rb^(+)∥Cl^(-)-H_(2)O 288.2 K固液相平衡研究  

Study on solidliquid phase equilibria in ternary system of Li^(+)(K^(+)),Rb^(+)∥Cl^(-)-H_(2)O at 288.2 K

作　　者：杨博 马珍 曾英[1] 严雄仲 李琪 侯元昇 于旭东[1] YANG Bo;MA Zhen;ZENG Ying;YAN Xiongzhong;LI Qi;HOU Yuansheng;YU Xudong(College of Materials and Chemistry&Chemical Engineering,Chengdu University of Technology,Chengdu 610059,China;Qinghai Salt Lake Industrial Co.,Ltd.,Golmud 816000,China)

机构地区：[1]成都理工大学材料与化学化工学院,四川成都610059 [2]青海盐湖工业股份有限公司,青海格尔木816000

出　　处：《无机盐工业》2024年第11期116-122,共7页Inorganic Chemicals Industry

基　　金：青海盐湖工业股份有限公司揭榜挂帅项目(10000000-23-ZC0609-0012)。

摘　　要：为了获取锂铷、钾铷共存氯化物体系在288.2 K时各盐结晶规律,采用等温溶解平衡法开展了三元体系Li^(+),Rb^(+)∥Cl^(-)-H_(2)O和K^(+),Rb^(+)∥Cl^(-)-H_(2)O在288.2 K下的固液相平衡研究,测定了溶解度、平衡液相的物化性质(密度、折射率),采用Schreinemakers湿渣法、X-ray粉晶衍射法、扫描电子显微镜-能谱仪等表征手段鉴定了共饱点处平衡固相组成,并绘制了相应的相图。结果表明:三元体系Li^(+),Rb^(+)∥Cl^(-)-H_(2)O在288.2 K时为简单体系,无复盐或固溶体生成,且RbCl的结晶相区大于LiCl·2H_(2)O。三元体系K^(+),Rb^(+)∥Cl^(-)-H_(2)O在288.2 K时为复杂体系,有固溶体(K,Rb)Cl生成且结晶相区最大,对比该体系在288.2、298.2、348.2 K时的多温相图发现,三个温度下均有固溶体(K,Rb)Cl生成,且固溶体(K,Rb)Cl结晶相区始终最大;随着温度升高,KCl、RbCl结晶相区变大,(K,Rb)Cl结晶相区变小。采用经验方程计算了两个体系平衡溶液的密度、折射率,计算结果与实验值吻合较好,最大相对误差小于0.02。In order to obtain the crystallization law of each salt in the coexistence chloride system of lithium and rubidium,potassium and rubidium at 288.2 K,the solid-liquid equilibrium of two ternary systems of Li^(+),Rb^(+)∥Cl^(-)-H_(2)O and K^(+),Rb^(+)∥Cl^(-)-H_(2)O at 288.2 K were studied by isothermal dissolution equilibrium method.The solubilities and physical properties(density,refractive index)of the system at 288.2 K were experimentally determined.The composition of the equilibrium solid phase at the invariant point was determined by wet residue method,XRD,SEM-EDS,the corresponding phase diagrams were constructed based on the experimental data.The results showed that the ternary system of Li^(+),Rb^(+)∥Cl^(-)-H_(2)O was a simple system without double salts or solid solution formed at 288.2 K.The crystallization region of RbCl was much larger than LiCl·2H_(2)O.The ternary system of K^(+),Rb^(+)∥Cl^(-)-H_(2)O was a complex system at 288.2 K with the solid solution(K,Rb)Cl was formed,and the crystallization region was the largest.Comparing the phase diagrams of the system of K^(+),Rb^(+)∥Cl^(-)-H_(2)O at 288.2,298.2 and 348.2 K,it was found that the solid solution(K,Rb)Cl was formed at all three temperatures,and the crystallization region of the solid solution(K,Rb)Cl was always the largest.With the increase of temperature,the crystallization region of KCl and RbCl became larger,and the crystallization region of(K,Rb)Cl became smaller.The density and refractive index of the equilibrium solution of these two systems were calculated by the empirical equation.The calculated results were in line with experimental values with the maximum relative error of less than 0.02.

关 键 词：相平衡 氯化锂 氯化钾 氯化铷 固溶体 

分 类 号：O642.4[理学—物理化学]