High-purity tungsten trioxide has the purity of at least 99.99%, with chemical purity from 99.99% to 99.9999%. The content will be required respectively as for some special elements, such as radioactive, alkali metal, heavy metals and gas elements, ect. It is insoluble in water, soluble in alkali.
The structure of high purity WO3 varies with temperature. They are triclinic, monoclinic, orthorhombic and tetragonal at different temperatures.
Health hazards: low toxicity. It is irritant to the eyes and skin. Workers who smelt tungsten steel and absorb tungsten trioxide may appear body exhaustion, unexplained fever, measles-like rash and proteinuria.
Explosion hazard: This product is non-flammable, but is excitant.
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