Phosphotungstic acid catalysts are widely used in catalyst, biological staining and reagent of various alkaloids, a nitrogenous base, phenol, protein and carbohydrate and other films.
Phosphotungstic acid having acidic and redox properties, is a versatile new catalyst has high catalytic activity, while its stability is good can do homogeneous and heterogeneous reactions, even as transfer catalyst. What’s more it is kind of green and pollution-free catalyst.
In the biological sample dyeing, phosphotungstic acid used for dyeing cell samples, often used in conjunction with hematoxylin and called phosphotungstic acid-hematoxylin dye. Some three-color staining reagents will also use with phosphotungstic acid.
At the same time it as biochemical reagents and chromatography reagents mainly in separate and identification drug, chemical toxicant and toxicology analysis, forensic identification and biological material analysis. Besides it is widely used as a precipitating agent, oxidizing agent and a color agent.

Tungsten Manufacturer & Supplier: Chinatungsten Online -http://www.tungsten-powder.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn
 

In recent years, study new catalytic materials are highly valued, and many researchers have tried to develop multi-functional catalyst to replace the conventional catalysts. The study found that the supported tungsten phosphide catalyst has excellent desulfurization and denitrification activity, especially for larger molecules organic sulfides and tungsten nitride has a higher denitrification and desulfurization activity.
Tungsten phosphide catalyst producing processes are as follow:
1. Making a certain amount of (NH4) 2W4O13 • 18H2O and (NH4) 2HPO (W and P atomic ratio of 1) to react to produce phosphorus tungstate which is the precursors of tungsten phosphide.
2. Putting the amount of tungstate solution into a certain amount of r-Al2O3, after impregnation, drying and calcination to give a white WP / r-Al2O3 catalyst precursor.
3. After heating and hydrogen reduction obtain phosphide catalyst.

Tungsten Manufacturer & Supplier: Chinatungsten Online -http://www.tungsten-powder.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn
 

Phosphotungstic acid is a pale yellow or gray fine crystal chemical which is the heteropolyacids of H3PW12O40 and it will usually appears in hydrate. Phosphotungstic acid structure generally called Keggin structure, this ion has a complete full tetrahedral symmetry, 12 tungsten atoms and oxygen atoms connected to form a cage in the middle is a phosphorus atom. Its physical properties are as follows: chemical formula: H3O40PW12.xH2O, molecular weight: 2880.05, molar mass: 2880.2g / mol, melting point: 89 ℃, soluble in alcohol, ether and water, and no significant toxicity, but it is slightly acidic with irritants.
Phosphotungstic acid chemical properties are as follows: an aqueous solution of phosphotungstic acid is a strong oxidant and the free acid is a strong acid. It is unstable when it contact with alkali metal, most common metals, metal oxides, strong reducing agents, carbonates and cyanide exposure. Besides it cannot compatibility with ammonia, aliphatic amines, alkanolamines, aromatic amines, amino compound, an organic acid anhydride, isocyanates, alkylene oxide, and epichlorohydrin.

Tungsten Manufacturer & Supplier: Chinatungsten Online -http://www.tungsten-powder.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn
 

Phosphorus and tungsten with different reaction condition can produce produces such as tungsten phosphide, tungsten diphosphide and so on.
Tungsten phosphide chemical formula is PW and the molecular weight is 214.8138, which is stable at room temperature and atmospheric pressure, but avoid to storage with oxide and other materials. Tungsten phosphide is general store at a closed place with room temperature, while dry and ventilated. There are some related system numbers which are as follows: CAS number: 12037-70-6, EINECS number: 234-864-7.
Tungsten phosphide produce processes are shown below:
1. Putting he amount of (NH4) 2W4O13 • 18H2O and (NH4) 2HPO in deionized water to dissolved, evaporated to dryness at 90 ℃, to obtain a viscous material.
2. Drying viscous material at 120 ℃, and then calcined at 500 ℃ for 5 hours to obtain a gray solid amorphous phosphorus tungstate.
3. Take 1.5ml phosphorus tungstate particles which are 20-40 mesh in hydrogen to heat to a certain temperature making phosphide reduction for four hours.
4. Passivation at room temperature in nitrogen stream which contain 0.5% oxygen for 12 hours.

Tungsten Manufacturer & Supplier: Chinatungsten Online -http://www.tungsten-powder.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn