Bismuth tungstate (Bi₂WO₆) is the most simple structure of Aurivillius type oxide. Its Bi₆s orbit and O₂p orbit are hybridized to form the valence band. The W₅d orbit forms a guide band, and its band gap is narrower (about 2.7eV). It can absorb some visible light and be excited. Therefore, the Bi2WO6 photocatalytic material is in the field of environmental purification and new energy development. Potential application value.

With the development of nanomaterials technology, semiconductor photocatalysis technology has broad prospects for development. In particular, the development of visible light responsive semiconductor photocatalytic materials further promotes the application of semiconductor photocatalysis technology in the field of environmental remediation.

A large number of domestic sewage and industrial waste water are discharged into rivers and lakes, resulting in eutrophication of water bodies, affecting the safety of water and living environment. The algae outbreak will cause the oxygen depletion in the water to lead to the death of the fish. The toxins released by some algae will poison the organisms. We should deal with the algae pollution quickly and effectively. It is an urgent need to control the water pollution.

With the development of shipping industry, marine and river water pollution caused by ships is becoming more and more serious. Some researchers have proposed a scheme of photocatalytic treatment of ship oil sewage by pre separation + fine filtration + deep oxidation.

At present, 50 to 60% of the world's tungsten is used for the manufacture of tungsten carbide. Among them, rock drills in mining tools, three-cone drills in oil extraction, and coarse-grain tungsten carbide used in the hobs of tunnel shield machines account for a considerable part of tungsten carbide.

At present, the main method of industrial decomposition of tungsten minerals is the NaOH decomposition process. This method must be used in extreme conditions (high temperature and high alkali) to realize the effective decomposition of tungsten ore. However, the acid decomposition method of tungsten ores has a very high thermodynamic reaction trend, but the decomposition is often incomplete due to the limitation of kinetics.