Tungstic Acid Boiling Point: 1

2900 INR

7800 INR

15000 INR

5.59 Gram per cubic meter (g/m3)

5.59 g/cm3 Gram per cubic centimeter(g/cm3)

For Industrial,Laboratory

Catalyst In common with the other heteropolyacids phosphotungstic acid is a catalyst and its high acidity and thermal stability make it a catalyst of choice according to some researchers.[13] It is in solution as a homogeneous catalyst, and as a heterogeneous catalyst "supported" on a substrate e.g. alumina, silica. Some acid catalysed reactions include: the homogeneous catalysis of the hydrolysis of propene to give 2-propanol the homogeneous catalysis of the Prins reaction the heterogeneous catalysis of the dehydration of 2-propanol to propene and methanol to hydrocarbons. Dyeing and pigments Phosphotungstic acid has been used to precipitate different types of dyes as "lakes".[14] Examples are basic dyes and triphenylmethane dyes, e.g. pararosaniline derivatives. Histology Phosphotungstic acid is used in histology for staining specimens, as a component of phosphotungstic acid haematoxylin, PTAH, and a trichromea reagents, and as a negative stain for imaging by a transmission electron microscope. Phosphotungstic acid haematoxylin (PTAH) Mallory described the reagent now generally known as PTAH in 1897.[16] PTAH stains tissues either reddish brown or blue depending on their type. This property of simultaneously staining two different colours is different from other haematoxylin reagents e.g. alum-haematoxylin. The role of phosphotungstic acid and the mechanism of staining is not fully understood. Interestingly the active component of haematoxylin is the oxidised form, haematin, although this rarely acknowledged in the literature which refer to haematoxylin staining. Phosphotungstic acid forms a lake with haematin.[17] The make a up of the reagent is uncertain, examination of a year old sample showed there to be three coloured components, blue, red and yellow.[18] These were not identified. Some investigations of a modela systems, reacting various compounds such as amino acids, purines, pyrimidines and amines with PTAH show that they give rise to different colours. Trichrome reagents In these reagents two or three basic dyes are used with phosphotungstic acid, in either a one step or multi-stage procedure. These reagents colour different tissue types different colours. Again the mechanism of staining is not fully understood. Some explanations include the proposal that phosphotungstic acid acts as a mordant to bind the dye to the tissue[20] or that alternatively it binds to tissue blocking it to dye molecules. Negative staining Adsorption onto tissue or the surface of viruses and its electron density are the bases of phosphotungstic acids action as a negative stain. This electron density arises from the presence of the 12 tungsten atoms which each have an atomic number of 74. The mechanism of the adsorption onto tissue has been proposed as being electrostatic rather than involving hydrogen bonding, as adsorption is not affected by pH. Analysis The potassium salt is only slightly soluble, unlike most other phosphotungstate salts, and has been proposed as a method for the gravimetric analysis of potassium. Precipitation of proteins In a number of analytical procedures one of the roles of phosphotungstic acid is to precipitate out proteins. It has been termed a "universal" precipitant for polar proteins.[23] Further studies showed that no precipitation occurred with I -amino groups but did occur with guanidino, Iu-amino and imidazole groups. Medicinal Very little work appears to have been carried out in this area. One example relates to liver necrosis in rats. Composite proton exchange membranes The heteropoly acids, including phosphotungstic acid, are being investigated as materials in composite proton exchange membranes, such as Nafion. The interest lies in the potential of these composite materials in the manufacture of fuel cells as they have improved operating characteristics

Industrial

1,473 i? C

1,473 Degree C

All India

All India

Eastern Europe

Australia

1000 Per Week

1000 Per Day

5000 Per Month

98%

90 %