Ammonium Paratungstate (APT) Calcination
APT calcined in air change course: T ≥ 240 ℃, as ammonium metatungstate (AMT)
300 ~ 350 ℃, ammonium tungsten bronze ATB
400 ℃, the hexagonal WO3
500 ℃, triclinic crystalline tungsten trioxide
APT purity, crystalline of hereditary
Calcination temperature, speed has a significant impact on the physical and chemical properties of the product
The higher the calcining temperature, the more coarse particle size obtained WO3
Rapid heated, larger specific surface area
Slowly heated, perfect crystalline, smaller specific surface area