The solvent extraction method is one of many methods of preparing ammonium paratungstate. The conversion rate of this method is high. And the mother liquor can be incorporated into the feed liquid for recycling. Also, the back extraction liquid can be used repeatedly. And it can even be used as agricultural fertilizer after reaching a certain ammonium concentration.
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Preparation of Ammonium Paratungstate by Solvent Extraction Method
Step One: Dissolve sodium tungstate solid in a small amount of deionized water and sour with concentrated hydrochloric acid to get yellow tungstic acid;
Step Two: Dissolve the generated yellow tungstic acid in ammonia water to get ammonium tungstate solution, and control the pH value of feed liquid higher than 9, the concentration of WO3 among 100~200g/L;
Step Three: Oscillate the feed liquid and organic solvent with a certain volume ratio in the separating funnel to contact with each other, analyze the concentration of water phase and organic phase after standing and separating the different phase, and digest the raffinate under certain conditions to produce ammonium paratungstate.
