Mg2+,K+//Cl-,B4O2-7-H2O四元体系288 K固液相平衡

采用等温溶解平衡法研究了288 K时Mg2+,K+//Cl-,B4O2-7-H2O四元体系的相平衡关系,测定该体系在288 K时平衡液相的溶解度和密度.依据实验测定的平衡溶解度数据及对应的平衡固相,绘制了该四元体系的平衡相图以及其密度-组成图.研究结果表明,四元体系Mg2+,K+//Cl-,B4O2-7-H2O 288 K时的固液相平衡实验中,有复盐KCI·MgCl2·6H2O生成,平衡相图中有3个共饱点,7条单变量曲线,5个结晶区,对应的平衡固相分别为MgB4O7·9H2O,K2B4O7·4H2O,KCl,MgCl2·6H2O,KCl·Mgcl2·6H2O.简要讨论了实验结果.     

Mg2+, K+//Cl-, B4O2-7-H2O四元体系288 K固液相平衡

采用等温溶解平衡法研究了288 K时Mg2+, K+//Cl-, B4O2-7-H2O四元体系的相平衡关系, 测定该体系在288 K时平衡液相的溶解度和密度. 依据实验测定的平衡溶解度数据及对应的平衡固相, 绘制了该四元体系的平衡相图以及其密度-组成图. 研究结果表明, 四元体系Mg2+, K+//Cl-, B4O2-7-H2O 288 K时的固液相平衡实验中, 有复盐KCl·MgCl2·6H2O生成, 平衡相图中有3个共饱点, 7条单变量曲线, 5个结晶区, 对应的平衡固相分别为MgB4O7·9H2O, K2B4O7·4H2O, KCl, MgCl2·6H2O, KCl·MgCl2·6H2O. 简要讨论了实验结果.     

298.16K下K+,Mg2+//Cl-,NO-3-H2O体系液固相平衡

采用等温溶解平衡法研究298.16K时四元体系K+,Mg2+//Cl-,NO-3-H2O的液固相平衡关系,测定了溶解度数据,并绘制出平衡相图.研究表明,在298.16K时,该体系相图有5个单盐结晶区、6条单变量溶解度曲线和3个零变量点.5个单盐结晶区分别对应于KNO3、KCl、Mg(NO3)2·6H2O、MgCl2O和复盐KCI·MgCl2·6H2O,其中KNO3的结晶区最大,MgCl2·6H2O的结晶区最小.     

K2B4O7-Na2B4O7-Li2B4O7-H2O四元体系273 K介稳相平衡

采用等温蒸发平衡法研究了四元体系K2B4O7-Na2B4O7-Li2B4O7-H2O在273 K时的介稳相平衡及平衡液相的密度. 研究发现该四元体系为简单共饱和型, 无复盐及固溶体形成, 根据溶解度数据绘制了相图, 相图中有一个共饱点E, 三条单变度曲线E3E, E2E, E1E; 三个平衡固相分别为K2B4O7·4H2O、Na2B4O7·10H2O 和LiBO2·8H2O. 并简要讨论了实验结果.     

Li+,Na+∥CO2-3,B4O2-7-H2O四元交互体系288K的相平衡

采用等温溶解平衡法对Li+,Na+∥CO2-3,B4O2-7-H2O四元体系进行288K相平衡研究.结果表明,该体系属简单共饱型,在288K等温溶解度相图中有二个共饱点,五条单变量曲线,平衡固相为Na2CO3@10H2O,Li2B4O7@3H2O,Na2B4O7@10H2O,Li2CO3.     

Mg^2＋，K^＋//Cl^-，B4O7^2——H2O四元体系288K固液相平衡

采用等温溶解平衡法研究了288K时Mg^2＋,K^＋//Cl^-,B4O7^2--H2O四元体系的相平衡关系,测定该体系在288K时平衡液相的溶解度和密度．依据实验测定的平衡溶解度数据及对应的平衡固相,绘制了该四元体系的平衡相图以及其密度一组成图．研究结果表明,四元体系Mg^2＋,K^＋//Cl^-,B4O7^2--H2O288K时的固液相平衡实验中,有复盐KCl·MgCl2·6H2O生成,平衡相图中有3个共饱点,7条单变量曲线,5个结晶区,对应的平衡固相分别为MgB4O7·9H2O,K2B4O7·4H2O,KCl,MgCl2·6H2O,KCl·MgCl2·6H2O．简要讨论了实验结果．     

Na+, K+//Cl-, B4O2-7-H2O四元体系273 K介稳相平衡

采用等温蒸发法研究了四元体系Na+, K+//Cl-, B4O2-7-H2O 273 K时的介稳相平衡与相图. 测定了该体系273 K平衡液相中各组分的溶解度及平衡液相的密度; 绘制了该体系的介稳相图. 该四元体系273 K相图由5条溶解度单变量线、4个结晶区及2个共饱和点组成. 体系无复盐或固溶体形成. 四个结晶区分别对应单盐NaCl、KCl、K2B4O7·4H2O 和Na2B4O7·10H2O. 共饱点E1处KCl、NaCl及Na2B4O7·10H2O三盐共饱和,所对应的平衡液相组成为w(Cl-)=29.15%, w(B4O2-7)=0.64%, w(K+)=5.97%, w(Na+)=15.55%; 共饱和点E2处盐KCl、Na2B4O7·10H2O和K2B4O7·4H2O的三盐共饱和, 所对应的平衡液相组成为w(Cl-)=22.84%, w(B4O2-7)=10.98%, w(K+)=28.01%, w(Na+)=1.53%. 同体系298 K时的稳定相图相比, 273 K时硼酸钠的结晶区变大, 而硼酸钾、氯化钠结晶区变小.     

五元体系Li+,Na+//CO32-,So42-,B4O72-H2O 288 K介稳相平衡研究

采用等温蒸发法研究五元体系Li+,Na+//CO32-,SO42-,B4O72--H2O 288 K介稳相平衡关系,测定在288 K条件下的介稳平衡溶液中各组分的溶解度和溶液密度,根据实验数据绘制相应的介稳平衡相图及密度组成图.研究结果表明该五元体系介稳相平衡中有复盐Na3Li(SO4)2·6H2O生成,其介稳相图中有4个共饱点,9条单变量曲线,6个Li2CO3饱和的结晶区分别为LiBO2·8H2O,Na284O7·10H2O,Na2CO3·10H2O,Na2SO4,Li2O4·H2O和复盐Na3Li(SO4)2·6H2O.     

Li~+,Na~+∥CO_3~(2-),B_4O_7~(2-)-H_2O四元交互体系288K的相平衡

采用等温溶解平衡法对Li~+,Na~+∥CO_3~2-,B_4O_7~2--H_2O四元体系进行288K相平衡研究.结果表明,该体系属简单共饱型,在288K等温溶解度相图中有二个共饱点,五条单变量曲线,平衡固相为Na2CO3·10H2O,Li2B4O7·3H2O,Na2B4O7·10H2O,Li2CO3.     

298.15和308.15 K时1,2-丙二醇+MCl (M=Na,K, Rb,Cs)+H2O三元体系的溶解度、密度和折光率

系统研究了1,2-丙二醇+MCl (M=Na, K, Rb, Cs)+H₂O三元体系在298.15 和308.15 K时的等温相平衡. 采用硝酸汞滴定法测定了体系中无机盐的含量, 采用安东帕RXA170 折光率仪及DMA4500 密度计测定了所有体系的折光率和密度数值. 报道了1,2-丙二醇质量分数从0增加到0.9过程中饱和及不饱和三元溶液体系的等温溶解度、密度和折光率数据. 实验结果发现, 随着1,2-丙二醇的不断加入, 饱和溶液的溶解度和密度均呈现出减小的趋势, 而折光率的变化则呈现出相反的趋势. 采用经验方程关联了不同醇水比条件下不饱和溶液的密度和折光率实验数据, 获得了较为理想的拟合结果. 本研究的开展充实了碱金属盐在混合溶剂中的热力学数据, 为相关溶液化学研究奠定了基础.     

273 K下Na2CO3-Na2SO4-Na2B4O7-H2O四元体系介稳相平衡的实验研究

采用等温蒸发法研究了四元体系Na2CO3-Na2SO4-Na2B4O7-H2O在273 K时的介稳相平衡及平衡液相的密度. 利用溶解度数据绘制了该四元体系273 K下的相图. 研究结果表明, 该四元体系有异成分复盐2Na2SO4·Na2CO3形成. 相图中有2个共饱点、5条单变量曲线和4个结晶相区. 4个结晶相区分别为盐Na2CO3·10H2O, Na2SO4·10H2O, Na2B4O7·10H2O和2Na2SO4·Na2CO3的结晶区. 复盐2Na2SO4·Na2CO3同时存在于包含Na2CO3-Na2SO4-H2O三元体系的其它四元体系或高元体系中. 在273 K介稳平衡相图中, 碳酸钠以Na2CO3·10H2O形式析出; 硫酸钠以Na2SO4·10H2O的形式析出; 硼酸钠的完整分子式为Na2B4O5(OH)4·8H2O. Na2CO3对Na2B4O7有盐析作用.     

Solid–Liquid Phase Equilibria in the Ternary Systems (LiBO 2 + NaBO 2 + H 2 O) and (LiBO 2 + KBO 2 + H 2 O) at 288.15 K and 0.1 MPa

Solid–liquid phase equilibria for the two aqueous systems (LiBO2 + NaBO2 + H2O) and (LiBO2 + KBO2 + H2O) at T = 288.15 K and p = 0.1 MPa were determined using the isothermal dissolution equilibrium method. The experimental results show that the phase diagrams consist of one two-salt co-saturated invariant point, two univariant solubility isotherms, and three crystallization fields. The two systems belong to simple co-saturated type, and neither double salt nor solid solution were found. The densities change regularly as the sodium metaborate (potassium metaborate) concentration increases in solution, and reach their maximum values at the invariant point. Based on the Pitzer and its extended Harvie–Møller–Weare (HMW) model, the solubilities for the ternary systems at 288.15 K were represented, and the calculated results agree well with the experimental values.     

Phase Equilibria of Quaternary System NaCl-NaBr-Na2B4O7-H2O at 348 K

The phase equilibria of quaternary system NaCl-NaBr-Na₂B₄O₇-H₂O at 348 K were studied by the isothermal equilibrium method. The solubilities and densities of the equilibrium solution were determined. According to the experimental data, the phase diagram, density-composition diagrams and water content diagram of the quaternary system at 348 K were plotted respectively. And the phase diagram consists of one univariant curve, two crystallization fields and without any invariant point of the quaternary system. The equilibrium solid phases of the two crysta- llization fields were Na(Cl, Br) and Na₂B₄O₇·5H₂O. The experimental results show that the quaternary system contained solid solution. The densities of the solution decrease with increasing NaCl concentration and increase with increasing NaBr concentration.     

Metastable Phase Equilibrium in the Reciprocal Quaternary System LiCl+MgCl2+Li2SO4+MgSO4+H2O at 348.15 K and 0.1 MPa

The metastable solubilities and the physicochemical properties including density and pH of the reciprocal quaternary system(LiCl+MgCl₂+Li₂SO₄+MgSO₄+H₂O) at 348.15 K and 0.1 MPa were determined using the isothermal evaporation method. The dry-salt diagram and water-phase diagram were plotted based on the experimental data. There are five invariant points, eleven univariant curves, and seven crystallization zones corresponding to hexahydrite, tetrahydrite, kieserite, bischofite, lithium sulfate monohydrate, lithium chloride monohydrate and lithium carnallite. Comparison between the stable and metastable diagrams at 348.15 K indicates that the metastable phenomenon of magnesium sulfate is obvious, and the crystallization regions of hexahydrite and tetrahydrite disappear in the stable phase diagram. A comparison of the metastable dry-salt phase diagrams at 308.15, 323.15 and 348.15 K shows that with the increasing of temperature the epsomite crystallization zone disappears from the dry-salt phase diagram of 303.15 K, and a new kieserite crystallization zone is presented at 348.15 K. The density and pH in the metastable equilibrium solution present regular change with the increasing of Jänecke index J(2Li⁺), and the calculated densities using the empirical equation agree well with the experimental values.     

丙烯腈、己二腈和丙腈与水的二元体系液-液相平衡数据的测定和关联(英文)

采用平衡法测定了丙烯腈+水、己二腈+水、丙腈+水三个二元体系在不同温度(303.15、313.15、323.15、333.15K)下的液-液相平衡数据;并采用NRTL(α=0.2,α=0.3)模型和UNIQUAC模型对液-液平衡数据进行了关联.结果显示,NRTL和UNIQUAC模型对三个二元体系在不同温度下的互溶度关联的目标函数值均小于1×10-17,实验值与计算值吻合较好,绝对偏差小于0.009,关联精度较高.该研究结果可为丙烯腈、丙腈和水三元平衡溶解度数据的模拟和预测提供可靠的基础数据,并对电解二聚法生产己二腈中电解液的分离提纯工艺具有一定的指导意义.     

Solid-liquid Metastable Equilibria in Quaternary System （NaCl＋Na2CO3＋Na2SO4＋H2O） at 273.15 K

The metastable phase equilibria of the quaternary system NaCl+Na2CO3+Na2SO4+H2O were studied at 273.15 K. The salts' solubilities, densities and pH values of the equilibrated solution in this system were determined. According to the experimental data, the metastable equilibrium phase diagram, the diagram of density vs. composition and pH vs. composition diagram were plotted. The phase diagram consists of five univariant curves, four crystallization fields and two invariant points. The four crystallization fields correspond to sodium carbonate decahydrate (Na2CO3·10H2O), sodium sulfate decahydrate(Na2SO4·10H2O), sodium chloride(NaCl) and burkeite(2Na2SO4· Na2CO3), respectively. The crystallization field of sodium sulfate decahydrate(Na2SO4·10H2O) is the largest, which indicates that sodium sulfate is easy to saturate and crystallize from solution at 273.15 K.     

Solid–Liquid Metastable Phase Equilibria in the Ternary System (MgCl<Subscript>2</Subscript> + MgSO<Subscript>4</Subscript> + H<Subscript>2</Subscript>O) at 323.15 K

The solubilities and the densities in the aqueous ternary system (MgCl₂ + MgSO₄ + H₂O) at 323.15 K were determined by the isothermal evaporation method. The phase diagram was drawn for this system at 323.15 K. The phase diagram consists of two invariant points, three univariant curves, and three crystallization regions corresponding to bischofite (MgCl₂ · 6H₂O), tetrahydrate (MgSO₄ · 4H₂O) and hexahydrite (MgSO₄ · 6H₂O). Neither double salts nor solid solution was found. Based on the Pitzer and Harvie–Weare (HW) model, the solubility equilibrium constants for the salts were fitted with the solubilities in this research work, and the solubilities of the ternary system at 323.15 K were calculated. Comparisons between the calculated and measured solubilities show that the predicted data agree well with the experimental results.     

LiNO_3-KNO_3-H_2O三元体系相平衡研究

本文采用等温法分别测定了KNO3-H2O体系的溶解度相图以及LiNO3-KNO3-H2O体系在273.15和298.15K的等温溶解度相图。结果表明在273.15K时LiNO3-KNO3-H2O体系的溶解度等温线有2条分支,对应的固相分别为KNO3和LiNO3·3H2O,共饱点组成为31.55wt%LiNO3和7.07wt%KNO3。该体系在298.15K的等温线有3条分支,对应的固相分别为KNO3,LiNO3和LiNO3·3H2O,2个共饱点组成分别为50.42wt%LiNO3,22.18wt%KNO3,和55.74wt%LiNO3,10.9wt%KNO3。