Ammonium metatungstate is a tungsten chemical in the form of highly soluble hydrated crystals, it is white or slightly yellow crystals which has no harmful components and slightly acidic. Due to its solubility in water, it can be used as raw material to produce tungsten trioxide.
Use ammonium paratungstate as raw material and heat to 220-280℃. After that it will lose ammonium and crystal water and transform into ammonium metatungstate. Continuously heat ammonium metatungstate to 600℃ until it loses all ammonium and crystal water, cool it down and crystallize, after spray drying it turns into yellow tungsten trioxide.
Ammonium metatungstate preparing tungsten trioxide is easy to operate, the finished product is of good uniformity. Tungsten trioxide can be used to made tungsten product and shielding matirials which is widely used in industry.
Tungsten trioxide is mainly used to calcinate to produce tungsten powder and tungsten carbide powder which is used to produce tungsten carbide products. Also it can be used as the raw material of pure tungsten, tungsten bar, tungsten wire, tungsten electrode, shielding material. It is also used as colorant in industry. In the ship building industry, tungsten trioxide is also used as corrosion resistant paintings and undercoating materials.