Ion Exchange Method Preparing Ammonium Paratungstate
Ion exchange technology has brought significant technological progress for ungsten smelting, and the preparation process of ammonium paratungstate (APT) by ion exchange method of is as follows:
1. Tungsten concentrate is treated with alkali to get alkaline sodium tungstate;
2. Add acidic substances into the alkaline solution with heating for neutralization treatment to get sodium tungstate;
3. Dilute the sodium tungstate to get pre-exchange solution;
4. Use weakly basic anion exchange resin to adsorb the tungsten in pre-exchange solution;
5. Use of desorbent for desorbing the weakly basic anion exchange resin with tungsten, and get the desorption;
6. Remove impurities in the desorption;
7. Evaporate and crystallize the solution to obtain ammonium paratungstate.
Using ion exchange method which is based on weakly basic anion exchange resin to prepare ammonium paratungstate has overcome the shortcoming of tungsten smelting with strong basic ion exchange technology of large water consumption, small work resin exchange capacity, large amount of waste water and hard to treat; and the advantages are shortening operation process, completing both impurity removal and transformation, with the sample equipment, high tungsten recovery, and finally get the qualified APT product.