Phosphotungstic heteropoly acid, also called Keggin type phosphotungstic acid, belongs to twelve phosphotungstic acid with the formula of H3PW12O40?nH20. It is a light yellow crystal or white powder. Different crystal water content cause difference in color. It is generally light yellow if it contains more crystal water; otherwise, it is white powder. It is soluble in water, alcohol, and ether, etc. Its solubility reaches the highest in ether. Keggin type phosphotungstic acid, as a solid acid with excellent catalytic performance,…
Tungsten Oxide
Cerium tungstate, also called cerium tungsten oxide (REO), is a yellow tetragonal crystal that is stable at normal temperature and pressure. Its CAS number is 13454-74-5; Molecular formula is Ce2O12W3; Molecular weight is 1023.74000; Relative density is 6.77g/mL (25/4°C); Melting point is 1089°C. It is insoluble in water. It is ferromagnetic below 30K.? Ecological data Usually it is not hazardous to water. However, on the basis of the principles of environmental protection, please do not discharge into environment without government’s…
Zirconium tungstate, also called tungsten zirconium oxide, is a kind of negative thermal expansion material (NTE material) that has excellent negative thermal expansion within the temperature range of 0.3 to 1050K. It is widely applied in integrated circuits, optics, ceramic matrix composites, metal matrix composites, dental materials, cement-based composites, aerospace engines, polyamide resin composites, and sensors, etc. The CAS number of zirconium tungstate is 16853-74-0; Molecular formula is ZrW2O8 and molecular weight is 586.89900. Producing Methods The producing method of…
Silver tungstate, also called silver tungsten oxide, is a kind of light yellow crystal or powder that is soluble in nitric acid, ammonia and potassium cyanide solution. It is mainly applied in catalyst, electronic and chemical industry. Its chemical formula is AgWO4; Molecular weight is 463.57400; CAS number is 13465-93-5. Properties 1. Can be easily reduced, but not it is not strong oxidant. 2. Can be decomposed by nitrate into white tungstic acid. 3. Can react with sulfide hydrogen to…
Magnesium tungstate is a kind of white powder with monoclinic structure. It dissolves in acids. But it is insoluble in water and alcohol. Its chemical formula is MgWO4; Molecular weight is 272.14; Density is 6.89g/cm3; CAS number is 13573-11-0. Magnesium tungstate is a type of self-activated fluorescent material, which can issue 253.7nm blue-white fluorescence under UV excitation. Therefore, it can be applied to produce X-ray fluorescent screen, luminous paint and fluorenscent powder. Producing Methods 1. Can be calcinated under 1000…
Copper tungstate, also called copper tungsten oxide, is a kind of light gray powder with octahedron configuration. Its CAS number is 13587-35-4. The molecular formula is CuWO4. The molecular weight is 311.38400. And the density is 7.5 g/mL (25/4 °C). It is red when hitting the melting point. CuWO4, with a structural distortion of wolframite, can be synthesized by the high temperature reaction between CuO and WO3. It is insoluble in ethanol, slightly soluble in acetic acid and soluble in…
Barium tungstate is a slightly toxic white powder with CAS No. of 7787-42-0, molecular formula of BaWO4, molecular weight of 385.16500, and relative density of 5.04 (at 15 °C). BaWO4 is stable in the air, slightly soluble in water, completely soluble in oxalic acid water solution. And it is easy to decompose in acid. Producing Methods 1. Obtained from the dissove of carbon barium in tungstic acid. 2. By reacting barium oxide or carbon barium with tungsten trioxide. 3. By…
Bismuth tungstate, also called bismuth tungsten oxide, is the simplest oxide in bismuth oxide-based layered perovskite with CAS No. of 13595-87-4, molecular formula of Bi2WO4, and molecular weight of 1161.47000. Currently, the main shapes of Bi2WO6 are like flake, nested, efflorescent, heliciform, tires, graded microspheres and nano-cage type. As a newly developed visible light catalyst, energy gap of Bi2WO6 is only 2.8eV. Developing Bi2WO6 of different sizes has become the research emphasis of Bi2WO6 as the property of material has…
Lithium tungstate is a kind of colorless triangular crystal with BeSiO3 crystal lattice. It is easily soluble in water and insoluble in ethanol. It is easy to decompose in acid. Its CAS No. is 13568-45-1. Molecular formula is Li2OW4. Molecular weight is 261.72000. Density is 3.71g/mL (25/4 °C). Li2OW4 can be prepared by dissolving WO3 in Li (OH) or Li2CO3 solution. Li2OW4 is stable under room temperature and pressure. But, it should also avoid light, fire and high temperature. It…
Tungsten silicide is an odorless blue-gray tetragonal crystal that dissolves in a mixture of nitric acid and hydrofluoric acid. But, it is insoluble in water and aqua regia. Its CAS No. is 12039-88-2, and molecular formula is Si2W, molecular weight is 240.01100, the melting point is 900°C, and the density is 9.88g/cm3. Tungsten silicide can be applied to produce anti-oxidation coating layer and the resistance wire poultice. Producing Method 1. Mix W powder and Si powder under mole ratio 1:2,…