Li＋, Na＋//SO42－, CO32－-H2O交互四元体系288 K介稳相平衡研究

采用等温蒸发法研究了四元体系Li^＋, Na^＋// SO₄^2－, CO₃^2－-H₂O 288 K介稳相平衡及平衡液相的密度、电导率、折光率、粘度和pH值, 测定了该四元体系288 K条件下介稳平衡溶液溶解度及物化性质. 根据实验数据绘制了相应的介稳相图. 研究发现: 该体系介稳平衡中有复盐Na₃Li(SO₄)₂•6H₂O形成. 其介稳相图中有3个共饱点, 7条单变量曲线, 平衡固相为: Li₂SO₄•H₂O, Na₂SO₄, Na₃Li(SO₄)₂•6H₂O, Li₂CO₃, Na₂CO₃•10H₂O. 复盐Na₃Li(SO₄)₂•6H₂O和一水硫酸锂(Li₂SO₄•H₂O)的结晶区较小, 而Li₂CO₃的结晶区最大; 该四元体系介稳平衡条件下未发现Na₂SO₄•10H₂O的结晶区.     

Li＋, Na＋//SO42－, CO32－-H2O交互四元体系288 K介稳相平衡研究

采用等温蒸发法研究了四元体系Li^＋, Na^＋// SO₄^2－, CO₃^2－-H₂O 288 K介稳相平衡及平衡液相的密度、电导率、折光率、粘度和pH值, 测定了该四元体系288 K条件下介稳平衡溶液溶解度及物化性质. 根据实验数据绘制了相应的介稳相图. 研究发现: 该体系介稳平衡中有复盐Na₃Li(SO₄)₂•6H₂O形成. 其介稳相图中有3个共饱点, 7条单变量曲线, 平衡固相为: Li₂SO₄•H₂O, Na₂SO₄, Na₃Li(SO₄)₂•6H₂O, Li₂CO₃, Na₂CO₃•10H₂O. 复盐Na₃Li(SO₄)₂•6H₂O和一水硫酸锂(Li₂SO₄•H₂O)的结晶区较小, 而Li₂CO₃的结晶区最大; 该四元体系介稳平衡条件下未发现Na₂SO₄•10H₂O的结晶区.     

Na+，K+//Br-，SO42--H2O四元体系323 K相平衡研究

采用等温溶解平衡法研究了四元体系Na⁺,K⁺//Br^-,SO₄^2--H₂O在323 K的相平衡关系,测定了该体系323 K的溶解度及平衡液相的密度,绘制了该体系的相图。研究发现：平衡体系存在复盐钾芒硝Na₂SO₄·3K₂SO₄的结晶区。其相图由3个共饱和点,7条单变量曲线和5个结晶区组成。相区分别对应NaBr·2H₂O、Na₂SO₄、K₂SO₄、KBr和Na₂SO₄·3K₂SO₄结晶区。其中复盐钾芒硝Na₂SO₄·3K₂SO₄,Na₂SO₄和K₂SO₄有较大结晶区,而NaBr·2H₂O和KBr有较小结晶区。对比了等温条件下四元体系Na⁺,K⁺//Cl^-,SO₄^2--H₂O相平衡结果。实验结果表明溴化物对硫酸盐有较强盐析作用。     

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⁺//CO₃^2-,SO₄^2-,B₄O₇^2--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,Na₂B₄O₇·10H₂O,Na₂CO₃·10H₂O,Na₂SO₄,Li₂SO₄·H₂O和复盐Na₃Li(SO₄)₂·6H₂O。     

五元体系Li+/Cl-，CO32-，SO42-，B4O72--H2O 298 K相关系实验研究

Zabuye saline lake, Tibet, China, is unrivalled in the world for its high concentration of chloride, sulfate, carbonate and borate of lithium, sodium and potassium. Always at the later stage of the evaporation of brines, most sodium and potassium salts are crystallized out, so the main components of brines can be described with the Li⁺, Mg²⁺/Cl^-, SO₄^2-, CO₃^2-, B₄O₇^2--H₂O system. As a part of study on the equilibrium of this complex system, the equilibrium solubilities and phase diagram of the quinary system Li⁺/Cl^-，CO₃^2-，SO₄^2-，B₄O₇^2--H₂O at 298 K were studied by isothermal dissolution equilibrium method. In the 3-dimentional solubility diagram or its projection diagram saturated with solid LiCl, there are four crystallization fields, four univariant curves and one invariant point. At the invariant point, the saturated solid salts are LiCl·H₂O, Li₂B₄O₇·3H₂O, Li₂CO₃and Li₂SO₄·H₂O. No double salt or solid solution is formed.     

四元交互体系Li+,Mg2+/Cl-,SO42--H2O25℃相平衡及物化性质研究

本文采用等温溶解平衡法研究了四元交互体系Li⁺,Mg²⁺/CI^-,SO-H₂O 25℃的机关系和平衡液相的物化性质(密度、粘度、电导率、折光率和pH).该体系25℃有七个相区Li₂SO₄·H₂O,MgSO₄·7H₂O,MgSO₄·6H₂O,MgSO₄·5H₂O,MgC1₂·6H₂O,LiCI·MgCl₂·7H₂O,LiCI·H₂O,十一条单变量线,五个共饱点。其中LiCI·H₂O+LiCI·MgCl₂·7H₂O+Li₂SO₄·H₂O为一致零变量点。与文献中的研究结果比较,我们得到两个新相区MgSO₄·6H₂O和MgSO₄·5H₂O.用经验和半经验公式计算了平衡液相的密度、折光率。由实验测定的溶解度数据求得了高锂浓度下的Pitzer参数。对该体系25℃溶解度进行了理论计算复证。     

液相OH•, NO3•和SO4•-与二甲基硫反应机理

利用激光闪光光解技术研究了液相二甲基硫(DMS)与OH^•, NO₃^•和SO₄^•-自由基的微观反应机理. 实验结果表明: 在pH 5～9时, OH^•氧化DMS生成DMSOH^•, DMSOH^•会与DMS反应生成(DMS)₂⁺; 而NO₃^•和SO₄^•-;会直接氧化DMS生成DMS^＋, 生成的DMS^＋会与DMS反应生成(DMS)₂⁺.(DMS)₂⁺与氧气的反应很慢, 它的衰减受pH影响较大.     

五元体系Li＋, K＋//, CO32- ,SO42- , B4O72- -H2O在288 K时的介稳相平衡研究

采用等温蒸发法研究了五元体系Li^＋, K^＋//, , -H₂O 在288 K时的介稳相平衡关系, 测定了该五元体系在288 K条件下的介稳平衡的溶解度和溶液密度, 根据实验数据绘制了相应的介稳平衡相图和水图. 相平衡研究结果表明该五元体系介稳相平衡中有复盐K₂SO₄•Li₂SO₄生成, 其介稳相图(Li₂CO₃饱和)有4个共饱和点, 9条单变量曲线, 6个Li₂CO₃饱和的结晶区分别为LiBO₂•8H₂O, K₂B₄O₇•4H₂O, K₂CO₃•3/2H₂O, K₂SO₄, Li₂SO₄•H₂O和复盐 K₂SO₄•Li₂SO₄.     

稀土配合物[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3的标准生成焓及热分解动力学研究

合成了高氯酸镨和咪唑(C₃H₄N₂), DL-α-丙氨酸(C₃H₇NO₂)混配配合物晶体. 经傅立叶变换红外光谱、化学分析和元素分析确定其组成为[Pr(C₃H₇NO₂)₂(C₃H₄N₂)(H₂O)](ClO₄)₃. 使用具有恒温环境的溶解-反应量热计, 以2.0 mol•L^－1 HCl为量热溶剂, 在T＝(298.150±0.001) K时测定出化学反应PrCl₃•6H₂O(s)＋2C₃H₇NO₂(s)＋C₃H₄N₂(s)＋3NaClO₄(s)＝[Pr(C₃H₇NO₂)₂(C₃H₄N₂)(H₂O)](ClO₄)₃(s)＋3NaCl(s)＋5H₂O(1)的标准摩尔反应焓为Δ_rH_m^ө＝(39.26±0.11) kJ•mol^－1. 根据盖斯定律, 计算出配合物的标准摩尔生成焓为Δ_fH_m^ө{[Pr(C₃H₇NO₂)₂(C₃H₄N₂)(H₂O)](ClO₄)₃(s), 298.150 K}＝(－2424.2±3.3) kJ•mol^－1. 采用TG-DTG技术研究了配合物在流动高纯氮气(99.99%)气氛中的非等温热分解动力学, 运用微分法(Achar-Brindley-sharp和Kissinger法)和积分法(Satava-Sestak和Coats-Redfern法)对非等温动力学数据进行分析, 求得分解反应的表观活化能E＝108.9 kJ•mol^－1, 动力学方程式为dα/dt＝2(5.90×10⁸/3)(1－α)[－ln(1－α)]^－1exp(－108.9×10³/RT).     

稀土配合物[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3的标准生成焓及热分解动力学研究

合成了高氯酸镨和咪唑(C₃H₄N₂), DL-α-丙氨酸(C₃H₇NO₂)混配配合物晶体. 经傅立叶变换红外光谱、化学分析和元素分析确定其组成为[Pr(C₃H₇NO₂)₂(C₃H₄N₂)(H₂O)](ClO₄)₃. 使用具有恒温环境的溶解-反应量热计, 以2.0 mol•L^－1 HCl为量热溶剂, 在T＝(298.150±0.001) K时测定出化学反应PrCl₃•6H₂O(s)＋2C₃H₇NO₂(s)＋C₃H₄N₂(s)＋3NaClO₄(s)＝[Pr(C₃H₇NO₂)₂(C₃H₄N₂)(H₂O)](ClO₄)₃(s)＋3NaCl(s)＋5H₂O(1)的标准摩尔反应焓为Δ_rH_m^ө＝(39.26±0.11) kJ•mol^－1. 根据盖斯定律, 计算出配合物的标准摩尔生成焓为Δ_fH_m^ө{[Pr(C₃H₇NO₂)₂(C₃H₄N₂)(H₂O)](ClO₄)₃(s), 298.150 K}＝(－2424.2±3.3) kJ•mol^－1. 采用TG-DTG技术研究了配合物在流动高纯氮气(99.99%)气氛中的非等温热分解动力学, 运用微分法(Achar-Brindley-sharp和Kissinger法)和积分法(Satava-Sestak和Coats-Redfern法)对非等温动力学数据进行分析, 求得分解反应的表观活化能E＝108.9 kJ•mol^－1, 动力学方程式为dα/dt＝2(5.90×10⁸/3)(1－α)[－ln(1－α)]^－1exp(－108.9×10³/RT).     

Die Polytherme des Quinären Systems Na+, K+, Mg2+/Cl−, SO//H2O im Bereich von +25° bis −10°C

Polythermal Curves of the Quinary System Na⁺, K⁺, Mg²⁺/Cl^?, SO//H₂O in Range between +25°C and ?10°C Proceeding from the 0°C, ?5°C and ?10°C isothermal curves of the quinary system Na⁺, K⁺, Mg²⁺/C1^?, SO//H₂O with saturation at NaCl, KCl, and carnallite, respectively, the polythermal curve is represented between 25°C and ?10°C. Within the new defined range of the polythermal curve the invariant five-salt-paragenesis NaCI, KCI, Glauber's salt (Na₂SO₄ · 10 H₂O), bitter salt (MgSO₄ · 7 H₂O), Schoenite (K₂SO₄ · MgSO₄ · 6 H₂O) can be found at ?7,2°C. It represents also the lowest temperature of formation of Schoenite in this system. It was necessary, moreover, to reconsider further univariant and invariant equilibrium solutions in the range between 25° and 0°C.     

The phase diagrams of the CdCl2-NaCl-H2O system at 298 K

Solid-liquid equilibrium of ternary system Cd²⁺, Na⁺//Cl^?-H₂O at 298 K were studied by an isothermal solution saturation method. Experimental results indicate that there are three univariant curves AE, EF, and FB, two invariant points E, F, and three crystallization fields in the ternary system. The ternary system has one double salt Na₂CdCl₄ · 3H₂O. The crystallization zones of equilibrium solid phases are CdCl₂ · H₂O (AEG field), Na₂CdCl₄ · 3H₂O (EFM field), and NaCl (FBN field), respectively. The composition of the invariant point E is CdCl₂ · H₂O and Na₂CdCl₄ · 3H₂O of which content was 52.70 and 4.11%, respectively. The composition of the invariant point F is Na₂CdCl₄ · 3H₂O and NaCl of which content was 27.92 and 14.95%, respectively. The density of solution in the ternary system show regular changes along with the increased cadmium concentration. The results indicated that CdCl₂ · H₂O possessed the highest solubility among those three salts, which means a strong transfer of Cd ion and a high pollution risk of soil environment. And the solubility of NaCl would be restrained as the three salts existing together.     

Solid‐Liquid Equilibria in the Quinary Na+, K+//Cl−, SO2−4, B4O2−7‐H2O System at 298 K

The solid‐liquid equilibria in the quinary system Na⁺, K⁺//Cl^?, SO^2?₄, B₄O^2?₇‐H₂O at 298 K had been studied experimentally using the method of isothermal solution saturation. Solubilities and densities of the solution of the quinary system were measured experimentally. Based on the experimental data, the dry‐salt phase diagram and water content diagram of the quinary system were constructed, respectively. In the equilibrium diagram of the quinary system Na⁺, K⁺//Cl^?, SO^2?₄, B₄O^2?₇‐H₂O at 298 K, there are five invariant points F1, F2, F3, F4 and F5; eleven univariant curves E1F1, E2F2, E3F3, E4F5, E5F2, E6F4, E7F5, F1F4, F2F4 F1F3 and F3F5, and seven fields of crystallization saturated with Na₂B₄O₇ corresponding to Na₂SO₄, Na₂SO₄·10H₂O, Na₂SO₄·3K₂SO₄ (Gla), K₂SO₄, K₂B₄O₇·4H₂O, NaCl and KCl. The experimental results show that Na₂SO₄·3K₂SO₄ (Gla), K₂SO₄ and K₂B₄O₇·4H₂O have bigger crystallization fields than other salts in the quinary system Na⁺, K⁺//Cl^?, SO^2?₄, B₄O^2?₇‐H₂O at 298 K.     

Solid-liquid phase equilibria at 50 and 75°C in the NaCl + MgCl2 + H2O system and the pitzer model representations

The solubilities in the NaCl-MgCl₂-H₂O system were determined at 50 and 75°C and the phase diagrams were constructed on the base of experimental data. One invariant point, two univariant curves, and two crystallization zones, corresponding to sodium chloride and dihydrate (MgCl₂ · 6H₂O) showed up in the phase diagrams of the ternary system, The mixing parameters θ_Na,Mg and Ψ_{Na,Mg, Cl} and equilibrium constant K _sp were evaluated in NaCl-MgCl₂-H₂O system by least-squares optimization procedure, in which the single-salt Pitzer parameters of NaCl and MgCl₂β⁽⁰⁾, β⁽¹⁾, and C ^φ were directly calculated from the literature. The results obtained were in good agreement with the experimental data.     

Phase Equilibria in the Systems Na+, K+||Cl--H2O and Na+, K+||Cl-, H2PO- 4-H2O at Temperatures of 0-100°C

Binary and ternary parameters of the Pitzer equation and also the thermodynamic potentials of solid phases and the solubility diagrams of ternary aqueous-salt systems Na⁺, K⁺||Cl^--H₂O and Na⁺, K⁺||Cl^-, H₂PO^- ₄-H₂O in the temperature range 0-100°C, which corresponds to the technological conditions of brine formation, were calculated.     

[Me3NC2H4OH]Zn2Cl5水溶液的激光光解研究

利用时间分辨激光光解技术研究了季铵盐型离子液体[Me₃NC₂H₄OH]Zn₂Cl₅(简写R-Zn₂Cl₅)的光解行为, 研究发现离子液体能被266 nm激光单光子电离, 生成阳离子自由基、[Zn₂Cl₅]^•中性自由基和水合电子, 观察到胆碱激发三线态的存在, 并测定了离子液体光电离的量子产额为0.04. 利用266 nm激光对离子液体、胆碱、氯化锌、氯化钠的光解行为比较, 发现胆碱阳离子的贡献很小, [Zn₂Cl₅]^－阴离子起主要作用. 采用氧化性自由基SO₄^•－引发离子自由基, 揭示其光电离机理, 测定离子液体的动力学反应速率常数, SO₄^•－ 460 nm的衰减速率常数为1.3×10⁹ L•mol^－1•s^－1, 320 nm离子自由基瞬态产物的生成速率常数为1.5×10⁹ L•mol^－1•s^－1, 两者很接近, 说明SO₄^•－自由基的衰减与瞬态自由基的生成是同步的.