中文摘要：

针对新疆硝酸盐矿组成,采用等温蒸发法分别研究了25℃及50℃下Na＋//NO3–,Cl–,SO42–-H2O四元体系的介稳相平衡、溶解度数据,并根据测得的数据绘制出了相应的介稳相图。结果表明：在25℃及50℃时Na＋//NO3–,Cl–,SO42–-H2O四元体系介稳相图存在四个单盐结晶区,五条单变量溶解度曲线和两个零变量点。四个单盐结晶区分别对应于NaCl、NaNO3、Na2SO4和NaNO3.Na2SO4.H2O。两个零变量点中,一个为NaCl,Na2SO4和NaNO3.Na2SO4.H2O的三盐不相称共饱点,另一个为NaCl,NaNO3和NaNO3.Na2SO4.H2O的三盐共饱点。与相同温度下平衡相图相比,25℃与50℃下介稳相图具有相同的变化趋势。介稳相图中NaCl饱和区扩大,复盐NaNO3.Na2SO4.H2O饱和区明显缩小,NaNO3饱和区基本没有变化。

英文摘要：

The metastable liquid-solid phase equilibria of the quaternary system Na＋//NO3-,Cl-,SO42＋-H2O,which is the composition of the nitrate deposits in Xinjiang of China,were studied at 25℃ and 50℃ by isothermal evaporation method.Based on the solubility data obtained,the metastable liquid-solid phase diagrams of the system at above two temperatures were plotted respectively.The results show that,in the metastable liquid-solid phase diagrams of the system at different temperatures,there are five univariant curves,two invariant points and four crystallization fields of single salt corresponding separately to NaCl,NaNO3,Na2SO4 and double salt NaNO3·Na2SO4·H2O.One of the invariant points is an incongruent point saturated with NaCl,Na2SO4 and NaNO3·Na2SO4·H2O,and the other is a congruent point saturated with NaCl,NaNO3 and NaNO3·Na2SO4·H2O.Compared the metastable liquid-solid phase diagrams obtained with equilibrium phase diagrams of the same system at 25℃ and 50℃,both the metastable phase diagrams obtained have the same variation trend： the NaCl crystallization regions in the metastable liquid-solid phase diagrams are bigger,the NaNO3·Na2SO4·H2O crystallization regions are smaller and those of NaNO3 do not change obviously.