At present, the method of extracting tungsten mostly adopts water immersion method. Before water immersion process, tungsten scrap needs to be sintered. The sintering process directly sinters the mixed powders. During the sintering process, the dust is discharged along with the flue gas, and the valuable metal tungsten is mixed in the dust, which results in the loss of valuable metal tungsten. The unreasonable ratio of raw materials to auxiliary materials leads to the low conversion rate of tungsten when tungsten waste is used to extract tungsten.

Due to the defects of concentrated sulfuric acid catalysis, scholars at home and abroad have successively used strong acid cation exchange resin, heteropoly acid, inorganic salts, solid superacid as catalysts to prepare tributyl citrate. Comparing various methods, chemists believe that Heteropoly salts with Keggin structure are the best catalytic scheme. For example, phosphotungstic acid with Keggin structure is an oxygen-containing polyacid bridged by heteroatom P and coordination atom W through oxygen atom coordination unit. It has both the function of acid catalysis and oxidation catalysis. It is a protonic acid with uniform strength and high catalytic activity.

Epoxy compounds are important intermediates in organic synthesis and chemical raw materials. The ternary ring of epoxy compounds has special tension, so it is easy to synthesize many substances needed by people through selective ring opening or functional group conversion. Epoxy compounds have been widely used in many fields such as fine chemical industry, petrochemical industry, organic synthesis, pharmaceuticals, spices and so on.

With the improvement of science and technology level and the progress of human development level, environmental pollution is becoming more and more serious, toxic and difficult to degrade. Pollutants are more and more widespread in the air, which is harmful to biological safety and ecosystem, and restricts the progress of society.

Since Andre Geim and Konstantin Novoselov won the Nobel Prize in Physics for their research on graphene in 2010, graphene-like transition metal sulfides MS₂ (M=Mo, W, Nb, Ta) have attracted wide attention due to their unique physical and chemical properties.

Tungsten oxide is an important semiconductor material. It is widely used in electrochromic devices, gas chromic devices, photovoltaic cells and other photovoltaic devices.

Due to the continuous consumption of fossil fuels and the increasingly prominent environmental problems, the search for clean and sustainable use of new energy has become an increasingly important topic. Among many new energy sources, hydrogen energy has become a research hotspot due to its high energy density, clean (water products) and sustainable utilization.

Tungsten carbide has a catalytic activity similar to platinum. It has stable physical and chemical properties and low cost. With people's attention to clean energy, the application of tungsten carbide in catalytic fields, such as direct methanol fuel cell, catalytic hydrogen evolution, supercapacitor and catalytic desulfurization, has attracted extensive attention of scientists. For example, tungsten carbide as a catalyst can partly replace or to some extent save precious metals such as platinum and palladium, and its application prospect is broad.

With the introduction of the concept of green chemistry, the enhancement of people's awareness of environmental protection and the emphasis on environmental protection, these inorganic acid catalysts are gradually being eliminated. Heteropoly acid and its salts catalysts are a new type of solid acid catalysts developed in recent years. Heteropoly acid is a kind of oxygen-containing polyacid formed by the bridging coordination of heteroatoms (such as P, Si, Fe, Co, etc.) and polyatoms (such as Mo, W, V) through oxygen atoms, such as phosphomolybdenum tungsten, phosphomolybdenum vanadium, silicotungstic acid and silicomolybdic acid.

With the development of social economy, there are many applications requiring smart frame circuit breakers to have higher electrical life. Therefore, it is necessary to develop a kind of material with strong resistance to arc erosion as static contacts, which can be used in pairs with AgW50 dynamic contacts, so as to greatly improve the electrical life of intelligent frame circuit breakers and meet the requirements of various applications.