Blue Tungsten Oxide Valence
Blue tungsten oxide (BTO) is an important raw material for production of tungsten powder. It doesn’t have a single tungsten oxide valence, and it is composed of W5+ and W6+ valences. With the reduction of oxygen content, valence of tungsten decreased gradually. Slight hydrogen ion etching, vacuum annealing and industrial hydrogen reduction treatment are processes of loss oxygen, but also change the process of tungsten from high valence to low valence, blue tungsten oxide can be two to three valence composition. Valence can be characterized by X-ray photoelectron spectrum.
Related Products:
Ammonium paratungstate (APT) is an important intermediate compounds of tungsten hydrometallurgical process, appearance is white crystalline powder, insoluble in water, soluble in alcohol and ether.
Ammonium metatungstate(AMT) is an important intermediate compounds of tungsten hydrometallurgical process, appearance is white crystalline powder, solubility in water is the largest in the tungsten compounds which over 300g WO3/100ml H2O (in 25℃).
Sodium tungstate, a tungstate of sodium, is useful as a source of tungsten. It is prepared from tungsten ores used to manufacture tungsten by reducing it.
Tungstic acid refers to hydrated forms of tungsten trioxide, WO3. The simplest form, the monohydrate, is WO3.H2O, the dihydrate WO3.2H2O is also known. The solid state structure of WO3. H2O consists of layers of octahedrally coordinated WO5(H2O) units where 4 vertices are shared.
Yellow tungsten oxide is a finely divided, yellow crystalline powder. It is produced by roasting ammonium paratungstate at closely controlled temperatures to drive off water and ammonia. Exact time and temperature control determine, to a large extent, the physical characteristics of yellow tungsten oxide.
Cesium tungsten bronze is inorganic nano material with good property in absorbing near-infrared with uniform grain size and dispersibility, it has strong absorbing function in near-infrared area with wave length 800~1200nm, also has high transmittance in visible light area with wave length 380~780nm.