物理化学学报Issue(2)：405-414,10.DOI:10.3866/PKU.WHXB201511192
拉曼光谱法研究Na+，Mg2+//SO42－，Cl－，H2O四元体系中SO42－离子缔合结构特征及其变化规律
Studies on the Characteristics and Behaviors of the Ion Association Structures of SO42-in Na+, Mg2+//SO42-, Cl-, H2O System by Raman Spectroscopy
摘要
Abstract
Stable and metastable solid-liquid equilibria phenomena and complex salt-forming behaviors exist in complex salt-water systems. To realize the relationship between salt-forming behavior and liquid structure, the characteristics of ion association structures of SO42-in Na+, Mg2+//SO42-, Cl-, H2O system and its binary, ternary subsystems were studied by Raman spectroscopy, combined with a Gauss-Lorentz peak fitting program. The spectrum experimental results show that there were two ion association structures of SO42- as non-associated SO42-and SO42-groups in the Na2SO4-H2O system, while in the MgSO4-H2O, MgSO4-MgCl2-H2O, and Na+, Mg2+//SO42-, Cl-, H2O systems, there were also Mg2+-H2O-SO42-and Mg2+-OSO32-structures. Non-associated SO42-was the main structure in theν1-SO42-band of binary (MgSO4 Na2SO4) and ternary (MgSO4-MgCl2-H2O) subsystems, and with varying SO42-concentration, these four types of SO42-ion association structure varied regularly. Likewise, the ion association structures of SO42-in the Na+, Mg2+//SO42-, Cl-, H2O system changed regularly during both the processes of NaCl crystal ization and isothermal evaporation. This was evident when, during the process of decreasing NaCl concentration and increasing MgSO4, the content of non-associated SO42-decreased, the chance of Mg2+-H2O-SO42-and Mg2+-OSO32-structure formation increased, and the SO42-group structure appeared in the astrachanite region. More importantly, the adaptive changes in solution structure during the progress of evaporation can result in the appearance of metastable phenomena. Further linear analysis showed that the concentration and Jänecke index (J) value of SO42-were positively related to the intensity and peak area of theν1-SO42-band, and the concentration of Mg2+affected the contents of four ion association structures in theν1-SO42-band mainly.关键词
SO42-/离子缔合结构/拉曼光谱/固液相平衡Key words
SO42-/Ion association structure/Raman spectroscopy/Solid-liquid phase equilibrium分类
化学化工引用本文复制引用
阎波,周桓,李文轩..拉曼光谱法研究Na+，Mg2+//SO42－，Cl－，H2O四元体系中SO42－离子缔合结构特征及其变化规律[J].物理化学学报,2016,(2):405-414,10.基金项目
The project was supported by the National Natural Science Foundation of China (21176189, U1407204), Natural Science Foundation of Tianjin, China (15JCYBJC23200), Training Program for Changjiang Scholars and Innovative Research Teams in University, China ([2013]373), and Innovative Research Team of Tianjin Municipral Education Commission, China (TD12-5004).国家自然科学基金(21176189, U1407204),天津市应用基础与前沿技术研究计划(15JCYBJC23200),教育部科研创新团队培育计划([2013]373)及天津市高等学校创新团队培养计划(TD12-5004)资助项目 （21176189, U1407204）
