三元体系KCl-ZnCl 2-H 2 O在323 K下的相平衡研究

Phase equilibrium of ternary system KCl-ZnCl2-H2O at 323 K

为了研究氧化锌矿氯化浸出液盐类溶解规律,文中采用等温溶解平衡法进行了323 K时三元体系KCl-ZnCl 2-H 2 O的稳定相平衡研究,并采用X射线粉晶衍射法和湿固相法对平衡固相的成分进行了鉴定,还对不同温度下该体系的溶解度进行了对比分析。研究发现KCl-ZnCl 2-H 2 O相平衡体系有复盐生成,为复杂三元体系,该体系相图中有2个共饱点,3条溶解度曲线,3个固相结晶区(分别对应了KCl,2KCl·ZnCl 2和ZnCl 2)。由溶解度数据和相图发现,氯化锌对氯化钾有明显的增溶效应。当氯化钾溶解度逐渐增大达最大值,再加入氯化锌,氯化钾的溶解度又开始降低并生成化学式为2KCl·ZnCl 2的复盐。

In order to study the dissolution of leaching salts of zinc oxide ore,the stable phase equilibrium of the ternary system KCl-ZnCl 2-H 2 O at 323 K was studied by means of isothermal dissolution equilibrium method.The equilibrium solid phase was identified by X-ray powder diffraction and wet solid phase method,and the solubility data of this ternary system at 323 K were compared and discussed at different temperatures.The results indicate that the ternary system has the formation of complex salts,which is a complex ternary system.The ternary system at 323 K has two invariant points,three univariant curves and three crystallization fields(corresponding to KCl,2KCl·ZnCl 2 and ZnCl 2,respectively).It is found from the solubility data and phase diagram that zinc chloride has an obvious solubilizing effect on potassium chloride.When the solubility of potassium chloride gradually increases to a maximum,the solubility of potassium chloride begins to decrease again after adding zinc chloride,and the compound salt of chemical formula 2KCl·ZnCl 2 is formed.