【作者】 慕思国；

【导师】 唐谟堂； 彭长宏；

【作者基本信息】 中南大学 ， 有色金属冶金， 2005， 硕士

【摘要】 本文采用等温溶解平衡法,研究了Me²⁺-NH₄⁺+SO₄^2--H₂O(Me²⁺代表Mn²⁺,Zn²⁺,Fe²⁺)、Mn²⁺-Zn²⁺-SO₄^2--H₂O、Fe²⁺-Zn²⁺-SO₄^2--H₂O和Fe²⁺-Mn²⁺-SO₄^2--H₂O六个三元体系在298K下的固液相平衡,绘制了平衡相图。测定了三元体系Zn²⁺-NH₄⁺-SO₄^2--H₂O、Mn²⁺-NH₄⁺-SO₄^2--H₂O、Fe²⁺-Zn²⁺-SO₄^2--H₂O和Mn²⁺-Zn²⁺-SO₄^2--H₂O饱和溶液的密度和pH值,并运用前苏联经验公式计算了这些三元体系饱和溶液的密度和结晶物的折光率,绘制了密度-组成、pH-组成曲线和折光率-组成曲线。 相平衡实验研究结果表明:在298K下,Mn²⁺-NH₄⁺-SO₄^2--H₂O三元体系固液平衡相图中,存在三条饱和曲线,对应的平衡固相分别是:MeSO₄·nH₂O、（NH₄）₂Me（SO₄）₂·6H₂O和（NH₄）₂SO₄;两个共饱和点,分别析出:MeSO₄·nH₂O和（NH₄）₂Me（SO₄）₂·6H₂O,（NH₄）₂ Me（SO₄）₂·6H₂O和（NH₄）₂SO₄;三个纯盐结晶区:（NH₄）₂ Me（SO₄）₂·6H₂O,MeSO₄·nH₂O和（NH₄）₂SO₄,一个混合盐晶区。在三元体系Mn²⁺-Zn²⁺-SO₄^2--H₂O饱和固液平衡相图中存在两条饱和曲线,对应的平衡固相分别是:ZnSO₄·7H₂O和MnSO₄·7H₂O;一个共饱和点,在共饱和点析出固相为ZnSO₄·7H₂O和MnSO₄·7H₂O;两个纯盐结晶区:ZnSO₄·7H₂O和MnSO₄·7H₂O,一个混合盐结晶区。在三元体系Fe²⁺-Zn²⁺-SO₄^2--H₂O饱和固液平衡相图中,存在两条饱和曲线,对应的固相分别是:ZnSO₄·7H₂O和FeSO₄·7H₂O;一个共饱和点,在共饱和点析出固相为ZnSO₄·7H₂O和FeSO₄·7H₂O;两个纯盐结晶区:ZnSO₄·7H₂O和更多还原

【Abstract】 In this paper, solubility phase equilibria were studied in the ternary systems of Me²+-NH₄⁺-SO₄²- -H₂O （ Me²+ is Mn²+, Zn²+, Fe²+）, Mn²+-Zn²+-SO₄²--H₂O, Fe²+-Zn²+-SO₄²--H₂O and Fe²+-Mn²+-SO₄²--H₂O at 298 K by the isothermal method of equilibrium. The densities and value of pH of the saturated solutions in the systems of Zn²+-NH₄⁺-SO₄²-"-H₂O, Mn²+-NH₄⁺-SO₄²-^-H₂O, Fe²+-Zn²+-SO₄²-"-H₂O and Mn²+-Zn²+-SO₄²-^-H₂O also were determined. According to Ezrokhin equations, the densities and refractive indexes of the equilibrium liquid phase were calculated. The solubility phase diagrams and physicochemical properties curves were drawn.The solubility isothermal phase diagrams of the ternary systems of Me²+-NH₄⁺-SO₄²-^-H₂O consist of three invariant branches, two invariant points and three crystallization fields. Corresponding to three crystallization fields, there have three kinds of solid phase, such as MeSO₄.nH₂O, （NH₄）₂SO₁4 and （NH₄）₂Me（SO₄）₂.6H₂O,respectively. There are just two invariant branches, one invariant point and two crystallization fields of the solubility diagrams of the ternary systems of Fe²+-Mn²+-SO₄²-"-H₂O, Fe²+-Zn²+-SO₄²- -H₂O and Mn²+-Zn²+-SO₄²-^-H₂O, respectively. The only difference is the equilinria solid phase, ZnSO₄.7H₂O and MnSO₄.7H₂O in the system of Mn²+-Zn²+-SO₄²--H₂O, ZnSO₄.7H₂O and FeSO₄-7H₂O in the system of Fe²+-Zn²+-SO₄²-"-H₂O, FeSO₄-7H₂O and MnSO₄.5H₂O in the system of Mn²+-Zn²+-SO₄²--H₂O.At the eutectic point, because plenty of crystalloid nucleus form or lots of crystals dissolve suddenly, concentration of the saturation solution have a marked change. At the same time, the refractive indexes of crystals also have a sudden change because of new crystals forming or existence crystals dissolving. The values of pH change slowly in all systems. The calculated results of the densities and refractive indexes agree with that of the experimental results.更多还原