Solid-liquid Metastable Equilibria in Quaternary System (NaCl+Na_2CO_3+Na_2SO_4+H_2O) at 273.15 K  

作　　者：WANG Rui-lin ZENG Ying 

机构地区：[1]Department of Chemical Engineering, Chengdu University of Technology, Chengdu 610059, P. R. China

出　　处：《Chemical Research in Chinese Universities》2010年第1期114-117,共4页高等学校化学研究（英文版）

基　　金：Supported by the National Natural Science Foundation of China(No.40673050);the Research Fund for the Doctoral Program of Higher Education from the Ministry of Education of China(No.20070616008);the Scholarship Leaders Training Fund from Sichuan Province,China(No.2008-140)

摘　　要：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（Na2SOn-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.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（Na2SOn-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.

关 键 词：Quaternary system Metastable phase equilibrium SULFATE 

分 类 号：O642.4[理学—物理化学] TQ114.14[理学—化学]