摘要
为获取粉煤灰含铝溶浸液中铝与共存钙、镁之间的作用规律,采用等温溶解平衡法开展了298.2 K时四元体系MgCl_(2)+CaCl_(2)+AlCl_(3)+H_(2)O相平衡研究,测定了平衡液相组成及平衡液相密度,同时,绘制了该四元体系的干基相图、水图、密度-组成图。研究发现:298.2 K四元体系MgCl_(2)+CaCl_(2)+AlCl_(3)+H_(2)O稳定相图由2个共饱点、4个结晶区以及5条单变量曲线组成,有复盐溢晶石(2MgCl_(2)·CaCl_(2)·12H_(2)O)生成,为复杂四元体系。4个结晶区分别对应3个单盐结晶区MgCl_(2)·6H_(2)O、CaCl_(2)·6H_(2)O、AlCl_(3)·6H_(2)O和1个复盐结晶区2MgCl_(2)·CaCl_(2)·12H_(2)O,结晶区按照AlCl_(3)·6H_(2)O、MgCl_(2)·6H_(2)O、CaCl_(2)·6H_(2)O、2MgCl_(2)·CaCl_(2)·12H_(2)O顺序依次减小,对应AlCl_(3)·6H_(2)O溶解度最小,2MgCl_(2)·CaCl_(2)·12H_(2)O溶解度最大。
In order to obtain the interaction law between aluminum and coexisting calcium and magnesium in leaching solution containing aluminum of fly ash,the phase equilibria of the quaternary system MgCl_(2)+CaCl_(2)+AlCl_(3)+H_(2)O was investigated by isothermal dissolution method at 298.2 K.The composition of liquid phase and density were determined.Meanwhile,the phase diagram,water diagram and density vs composition diagram of the quaternary system were drawn,respectively.It was found that the stable phase diagram of the quaternary system MgCl_(2)+CaCl_(2)+AlCl_(3)+H_(2)O consisted of two invariant points,four crystallization regions and five univariate curves,which belonged to a complex system with the double salt of tachyhydrite formed.These four crystallization regions corresponded to single salts MgCl_(2)·6H_(2)O,CaCl_(2)·6H_(2)O,AlCl_(3)·6H_(2)O and double salt 2MgCl_(2)·CaCl_(2)·12H_(2)O,respectively.The crystallization regions decreaseed in the order of AlCl_(3)·6H_(2)O,MgCl_(2)·6H_(2)O,CaCl_(2)·6H_(2)O and 2MgCl_(2)·CaCl_(2)·12H_(2)O,the solubility of AlCl_(3)·6H_(2)O was the smallest and the solubility of 2MgCl_(2)·CaCl_(2)·12H_(2)O is the highest.
作者
何志意
方滇东
郑秋风
任思颖
罗军
于旭东
HE Zhiyi;FANG Diandong;ZHENG Qiufeng;REN Siying;LUO Jun;YU Xudong(Sichuan Metallurgical Geological Survey and Design Group Co.,Ltd,Chengdu 610051,China;College of Materials and Chemistry&Chemical Engineering,Chengdu University of Technology,Chengdu 610059,China)
出处
《矿产保护与利用》
2022年第6期153-158,共6页
Conservation and Utilization of Mineral Resources
