Tungsten carbide is a compound composed of tungsten and carbon. It is mainly used in the production of cemented carbide. At present, the way to produce tungsten carbide powder is the two step method, that is, first we use hydrogen to reduce tungsten oxide to tungsten powder, the tungsten powder is then carbonized and carbonized into tungsten carbide at high temperature. But this method is not easy to produce ultrafine tungsten carbide powder, not to mention the production of ultrafine particles of tungsten carbide - metal cobalt composite powder.

The surface effect means that when the tungsten oxide particles are in the small size range of 1-100 nm, as the diameter of the tungsten oxide particles becomes smaller, the number of atoms on the surface of the nano particles is rapidly increased.

Defective tungsten oxide nanomaterials have drawn wide attention in the tungsten products industry because of their unique structural properties and excellent properties. The use of traditional solvothermal method can be prepared with defective tungsten oxide nanomaterials. Defective tungsten oxide nanomaterials synthesis method is as follows:

Unlike the stoichiometric tungsten oxide color, the defective tungsten oxide nanomaterials are light green or blue with an extra broadband absorption between 400 and 700 nm. This increased absorption peak is due to the presence of oxygen vacancies leading to a new band in the conduction band.

In the prior art, the preparation of ammonium paratungstate industrial process from tungsten mineral raw materials by caustic soda or soda decomposition to obtain crude sodium tungstate solution; purification by solution ion exchange or solvent extraction transformation to obtain the pure ammonium tungstate solution; then through evaporation and crystallization, APT products.

Recovering tungsten from tungsten waste has become an important measure to alleviate the shortage of raw materials. At present, the main ways to treat tungsten waste at home and abroad include mechanical crushing, electrolysis, alkali leaching, sodium roasting and zinc melting. Among them, sodium roasting technology is more mature and has wide applicability to waste tungsten materials. Therefore, this method is generally used to recycle tungsten carbide and various kinds of tungsten.