(1. 中南大学 冶金科学与工程学院，长沙 410083；2. 稀有金属冶金与材料制备湖南省重点实验室，长沙 410083)
摘 要: 绘制25 ℃时W-H2O系、Mo-H2O系以及W-Mo-H 2O系中存在的物种随pH值、钨、钼浓度变化的热力学平衡图，并总结其变化规律。热力学分析表明：W-Mo-H2O系中的钨、钼在酸化过程中一般经历从单体离子到杂多酸根离子再到同多酸根离子的转变过程。在pH值为6.5~7.5的范围内，钨转变成聚合离子的程度均高于钼，表明单钨酸根离子的聚合能力强于单钼酸根离子的；而在pH值为3.0~6.5的弱酸性区间内，溶液中形成浓度较高的钨钼杂多酸根离子，这对于钨钼分离极其不利。
关键字: W-Mo-H 2O系；钨钼分离；热力学分析；钨钼杂多酸；聚合离子
（1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China;2. Hunan Key Laboratory for Metallurgy and Material Processing of Rare Metals, Central South University, Changsha 410083, China）
Abstract:The thermodynamic equilibrium diagrams for the distribution of species at different pH values, tungsten and molybdenum concentrations in W-H2O, Mo-H2O and W-Mo-H2O systems at 25 ℃ were drawn, and the variational regularities of species were also analyzed. The thermodynamic analysis shows that the tungsten and molybdenum are transformed from monomeric anions to heteropolyanions, then to isopolyanions during the acidification process in W-Mo-H2O system. The polymeric degree of tungsten is significantly higher than that of molybdenum in the pH range from 6.5 to 7.5, which indicates that the polymeric ability of monotunstates is stronger. At pH values of 3.0-6.5, the heteropolymolybdotungstate ions with higher concentration are formed, which is extremely unfavorable to the separation of tungsten and molybdenum.
Key words: W-Mo-H2O system; separation of tungsten and molybdenum; thermodynamic analysis; heteropolymolybdotungstate; polymeric ions
