Ion exchange process for preparing ammonium tungstate solution

[0017] Example 1: Prepare 600g of macroporous weakly basic anion resin (dry resin, the same below), using PH=2 containing SO 4 2- The acidic solution to regenerate the above resin. Take 16L of pure sodium tungstate solution, its WO 3 The content is 69g/l, with SO 4 2- Adjust the acidity of the sodium tungstate solution to pH 4.2, at this time WO 3 The content is 26g/l. The acid-adjusted sodium tungstate solution is passed through the regenerated resin for adsorption. The adsorbed negative tungsten resin is washed with pure water until the PH value is neutral; the concentration of ammonia water is 7mol/L and NH 4 5L of the mixed solution with a Cl concentration of 2mol/L, first use a linear flow rate of 15cm/min and then gradually reduce to 3cm/min to desorb the neutral negative tungsten resin, and the obtained ammonium tungstate solution is evaporated and crystallized to obtain APT. The crystallization rate is 94%, and the quality reaches the APT-0 standard.

[0018] Example 2: Prepare 600g of a macroporous weakly basic anion resin, using pH=1.5 containing SO 4 2- The acidic solution to regenerate the above resin. Take 19L of sodium tungstate solution, its WO 3 The content is 69g/l, the mass ratio of tungsten and molybdenum is W:Mo=6500, and the PH=2 containing SO4 2- Acid solution, adjust the pH of the above sodium tungstate solution = 4.9, its WO 3 The content is 26.4g/l. The acid-adjusted sodium tungstate solution is passed through the regenerated resin for adsorption. The adsorbed negative tungsten resin is washed with pure water until the PH value is neutral; the concentration of ammonia water is 8mol/L and NH 4 NO 3 6L of the mixed solution with a concentration of 1.5mol/L, first at a linear flow rate of 14cm/min and then gradually reduced to 2cm/min to desorb the neutral negative tungsten resin, and the obtained ammonium tungstate solution is evaporated and crystallized to obtain APT. Its crystallization rate is 93%, and its quality reaches APT-0 standard.

[0019] Example 3: Prepare 600g of macroporous weakly basic anion resin, using Cl containing PH=1.0 - The hydrochloric acid solution to regenerate the above resin. Take WO 3 APT crystallization mother liquor 15L and WO with a content of 48.58g/l 3 16L of slag washing water with a content of 25g/l, the mass ratio of tungsten and molybdenum in the solution is WO 3 :Mo=3600; add 0.5% Na with the volume ratio of tungsten-containing solution 2 S solution, use 2mol/L dilute hydrochloric acid and pH 2.5 containing SO4 2- Of the production waste liquid, adjust the pH of the above solution = 4.21, at this time WO 3 The content is 27g/l. The acid adjusted solution is passed through the above-mentioned regenerated resin for adsorption. The adsorbed negative tungsten resin is washed with pure water until the PH value is neutral; the concentration of ammonia water is 10mol/L and NH 4 NO 3 5L of the mixed solution with a concentration of 2.2mol/L, desorb the neutral negative tungsten resin at a linear flow rate of 14cm/min and then gradually reduce to 2.5cm/min, and the obtained ammonium tungstate solution is evaporated and crystallized to obtain APT , Its crystallization rate is 92%, and its quality reaches APT-0 standard.