Industrial grade tungstic acid is an intermediate compound of ammonium paratungstate (APT) in powder metallurgy.
Preparation of Industrial Grade Tungstic Acid
Step 1: Add tungstic acid raw material with a purity of 99.95% into the inorganic acid solution, the mass ratio of the inorganic acid solution to the tungstic acid raw material is 1:1 to 2:1, ultrasonic irradiation oscillation for 3h-6h. The temperature is controlled at the range of 20°C~40°C, suction filtration to obtain filter cake solid;
Step 2: Put the filter cake solid obtained in the first step into the inorganic acid solution. The mass ratio of the inorganic acid solution to the filter cake solid is 1:1 to 3:1, ultrasonic irradiation oscillation for 5h-10h, the temperature is controlled at the range of 30°C~50°C, filtration to get solid;
Step 3: Place the solid obtained in the second step into deionized water and wash for 2 or 3 times, suction filtration under reduced pressure. The filter cake is pressed to dry and vacuum dried at 60°C~80°C for more than 10 hours to obtain tungstic acid with a purity of 99.999%.
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