异戊醇萃取分离钼酸钠溶液中微量硅的研究

对钼酸钠溶液中的微量杂质硅的萃取分离进行了研究。结果表明,在一定条件下,溶液中的硅能够被异戊醇非常高效地去除。试验研究了最佳的反应条件以及影响萃取分离的主要因素。在硅钼杂多酸形成阶段,当初始反应的pH为0.7~1.0,低浓度和高浓度的钼酸钠与硅酸反应都比较完全;用异戊醇对硅钼杂多酸进行萃取分离时,溶液中氢离子、硅、钼酸钠的浓度等对萃取率均有影响;当水相的起始pH为0.5左右,硅和钼酸钠质量浓度分别为40 mg/L和50 g/L时,经过三级逆流萃取,硅的萃取率可达98%以上。

Study on the extraction and separation of trace silicon from sodium molybdate solution with iso-amyl alcohol

The solvent extraction of trace silicon as an impurity from sodium molybdate solution with isoamyl alcohol was studied.The experimental results indicated that silicon can be extracted and separated very effectively from the solution by the proposed method.The key factors influencing the successful extraction of silicon were respectively studied and the best operating conditions were obtained.For the formation of heteromolybdosilicic acid,the optimum pH range is 0.7-1.0 in both low and high concentrations of sodium molybdate.The extraction rate of heteropoly acid using iso-amyl as extractant was much influenced by the hydrogen ions in the solution and the concentrations of silicon and sodium molybdate solution.More than 98% silicon was separated by three stage countercurrent extraction in pH 0.5 and the concentration of 40 mg/L for silicon and 50 g/L for sodium molybdate solution.