It is known that in 1950s, producing tungsten powder mainly used tungstic acid and yellow tungsten oxide as raw material. Until 1960~1970s, America, France, Holland, British used blue tungsten oxide as raw material instead of tungstic acid and yellow tungsten oxide as raw material. The study for blue tungsten oxide starts in China since 1970s. There are many factors which can affect tungsten powder property, of which producing method and raw material are the most important. Producing finer grain size of tungsten powder need tungsten oxide with low oxygen content, the coarser grain size need tungsten oxide with higher oxygen content. As a result, blue tungsten oxide producing method with low research cost, high property and less environmental pollution has drawn much attention.

Ammonium Paratungstate Reduction Producing Blue Tungsten Oxide

Producing Theory: Use the existing rotary furnace, by adjusting the technology and optimizing technological parameter without injecting hydrogen. With the already exist ammonia, under certain temperature condition, ammonia will split out of hydrogen, it will have mild reduction on the splitting to make the fitted blue tungsten oxide.

Producing Method: Use APT as raw material, under the special technological condition without injecting hydrogen, With the already exist ammonia, under certain temperature condition, ammonia will split out of hydrogen, it will have mild reduction on the splitting to produce BTO.