Removal of tungsten from the sodium molybdate solution using nascent MnO2

Abstract

Tungsten is hard to be separated effectively from molybdate solution due to their extremely similar chemical properties. In this research, a novel tungsten removal method was developed to remove tungsten from the molybdate solution using nascent MnO2. Through comparing different preparation method of nascent MnO2, in situ synthesized method was chosen as the optimal preparation route. And the effects of reaction temperature, Mn addition, pH value, reaction time and Mo/W mass ratio of solution on the tungsten removal were also investigated. The experimental results showed tungsten could be selectively removed quickly from molybdate solution. On the optimal reaction conditions of reaction temperature 25°C, 50 times theoretical reagent amount of Mn addition, pH value 8.0–8.5 and reaction time 1.0h, 95% of tungsten can be removed from the molybdate solution with different Mo/W mass ratio and the Mo loss can be controlled to only about 5%. The results showed that nascent MnO2 was a high-efficiency tungsten removal reagent from the molybdate solution.