钨酸盐溶液中钼的硫化理论与实践

Theory and Practice of Sulfuration of Molybdate in Tungstate Solution

针对钨酸盐溶液中钼的硫化进行了系统的热力学分析和试验研究。热力学分析表明 ,在一定的条件下MoO2 - 4可以完全被硫化为MoS2 - 4,其硫化程度随溶液pH的降低和硫化剂用量的增加而提高 ,并查明了MoS2 - 4、MoOS2 - 3、MoO2 S2 - 2 、MoO3S2 - 和MoO2 - 4随溶液pH值及硫化剂用量变化的分布情况。同时通过试验研究进一步考察了溶液pH值、S2 - 用量、硫化温度及硫化时间对硫化效果的影响 ,查明了钨酸盐溶液中钼的硫化规律 ,并获得了合理的硫化工艺条件 ,即在预调pH <7.5、S2 - 游离 1.5～ 2 .0g L或预调pH =7.5～ 8.0、S2 - 游离 2 .0～ 3 .0g L的条件下 ,在 70～ 75℃下保温 1.5～ 2 .

The sulfuration of molybdate in tungstate solution has been studied through thermodymic analysis and experiment in detail. The results of thermodymaic analysis show that MoO 2- 4 can be sulfurized into MoS 2- 4 thoroughly under certain conditions and the sulfuration ratio of Mo increases with the decreasing of pH of the solution and the increasing of the amount of S 2- . The variation of the distribution of MoS 2- 4 ,MoOS 2- 3, MoO 2S 2- 2,MoO 3S 2- and MoO 2- 4 with the pH of solution and the amount of S 2- are also obtained through thermodymaic analysis. At the same time, the influences of the pH of solution,the amount of S 2- ,the temperature and the duration on sulfuration results are studied through experiment, and the proper sulfuration conditions have been obtained at last, that are, pH<7.5, 1.5～2.0 g/L S 2- free or pH=7.5～8.0,2.0～3.0 g/L S 2- free, 70～75 ℃, 1.5～2.0 h.