298.16K时Na^+,Mg^(2+)//Cl^-,SO_4^(2-),NO_3^-,H_2O体系中NaCl饱和区域相平衡

Liquid-solid Phase Equilibrium for the Quinary System Na^+,Mg^(2+)//Cl^-,SO_4^(2-),NO_3^-,H_2O Saturated with NaCl at 298.16 K

采用等温溶解平衡法研究了五元体系Na+,Mg2+//Cl-,SO42-,NO3-,H2O在298.16K下氯化钠饱和平衡体系的溶解度,获得了相应的投影干盐图、氯图和水图.研究结果表明,在298·16K下氯化钠饱和时,该五元体系投影干盐图由8个二盐共饱和的双变面、13条三盐共饱的单变线和6个四盐共饱的零变点构成,存在两种复盐,8个二盐共饱双变面分别对应于NaCl+NaNO3,NaCl+Na2SO4,NaCl+MgCl2·6H2O,NaCl+MgSO4·Na2SO4·4H2O,NaCl+Mg(NO3)2·6H2O,NaCl+NaNO3·Na2SO4·2H2O,NaCl+MgSO4·7H2O和NaCl+MgSO4·(1~6)H2O.讨论了该相图在新疆硝酸盐矿开发利用过程中的应用.

Solubilities in the system Na^＋, Mg^2＋//Cl^-, SO3^2-, NO3^-, H2O saturated with NaCl were investigated by isothermal method at 298. 16 K. According to the experimental data, the solvent-free, NaCl-free and water projection phase diagrams of this system were plotted. In this system, eight crystallization fields with two saturated salts were observed： MgSO4 · Na2SO4 · 4H20 ＋ NaCl, NaNO3 ＋ NaCl, NaNO3 · Na2SO4 · 2H2O ＋ NaCl, MgCl2 · 6H2O＋ NaCl, Na2SO4 ＋ NaCl, Mg（NO3）2 · 6H2O ＋ NaCl, NaCl ＋ MgSO4 · 7H2O and MgSO4 · （1---6） H2O ＋ NaCl. The respective crystallization areas are being separated from each other by thirteen univariant curves with three saturated salts which intersect in six invariant points corresponding to NaCl ＋ Na2SO4 ＋ Na2SO4 · MgSO4 · 4H2O ＋ Na2SO4 · NaNO3 · 2H2O, NaCl ＋ NaNO3 ＋ Na2SO4 · MgSO4 · 4H2O ＋ Na2SO4 · NaNO3 · 2H2O, NaCl ＋ NaNO3 ＋ Na2SO4 · MgSO4 · 4H2O ＋ MgSO4 · 7H2O, NaCl ＋ NaNO3 ＋ Mg（NO3）2 · 6H2O ＋ MgSO4 · 7H2O, MgSO4 · （1-6）H2O ＋ Mg（NO3）2 · 6H2O ＋ MgSO4 · 7H2O ＋ NaCl, MgSO4 · （1-6）H2O ＋ NaCl ＋ MgCl2 · 6H2O ＋ Mg（ NO3 ）2 · 6H2O. Application of these phase diagrams were discussed for industry.