采用等温溶解平衡法研究了五元体系Na^+,Mg^2+//C^-,SO4^2-,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.