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99.95% tungsten trioxide can be prepared by normal temperature extraction – normal temperature reextraction method to obtain ammonium paratungstate (APT) and then heat APT to a certain temperature for tungsten trioxide powder. Producing Method The wolframite is pressure boiled to obtain sodium tungstate solution. After pretreatment, extract active tungsten from the solution with organic reagents (various amines). That means purification and transformation effect are available. The obtained pure tungsten solution is treated by evaporative crystallization to get high-purity APT. Then,…

99.9% tungsten trioxide is a yellow powder that is insoluble in water and soluble in alkali. It can be used to produce tungsten powder. Tungsten Trioxide Hydrogen Reduction Tungsten trioxide hydrogen reduction, a traditional high-volume production technology, is one of the producing methods of tungsten powder. The process is generally divided into two stages: 1. The first stage: Reduce tungsten trioxide to tungsten dioxide under 500~700°C. 2. The second stage: Reduce tungsten dioxide to tungsten powder under 700~900°C. The detailed…

99.99% tungsten trioxide is a yellow powder that can show different crystal structures at different temperatures. It is mainly applied in the following fields: 1. To prepare tungsten powder and its downstream products, such as tungsten metal products (tungsten wire, tungsten electrode, etc.) and tungsten carbide materials (knives, molds, etc.). 2. As a catalyst, for a variety of organic synthesis. 3. Used as a colorant in high temperature transparent material, dielectric and piezoelectric ceramic, high-grade ceramic and the ion-coating activator…

Analytical pure tungsten trioxide is AR tungsten trioxide that can be used as an analytical reagent. It is suitable for a variety of important analysis and general research work. For example, it is commonly used in general laboratories, research institutes and other places to prepare ordinary solution in quantitative analysis. It should be sealed and stored in a dry place. What is AR? AR, analytical reagent, is a type of purity of chemical reagents. There are fewer impurities in the…

Large grain size tungsten trioxide (wide spec tungsten trioxide) is a lower grade of tungsten trioxide powder that has the same density with tungsten trioxide, but at a much lower cost than pure WO3 powder. Tungsten trioxide with large grain size is specifically developed for various applications where the high density of tungsten is desired yet extreme purity is not required. Application of Large Grain Size Tungsten Trioxide To be applied for producing tungsten counterweight such as golf head counterweight,…

High density tungsten trioxide refers to the tungsten trioxide powder with higher density than common WO3 powder. It is applied for somewhere requires high density. Tungsten trioxide can be prepared from tungsten concentrate. The main methods to measure the content of tungsten trioxide in tungsten mine include gravimetric, volumetric, colorimetry, polarography, and atomic absorption spectrometry method, etc. In general, gravimetric and volumetric methods are suitable for the high levels of tungsten content. For the low level of tungsten content, colorimetry,…

High-purity ultrafine tungsten trioxide refers to the tungsten trioxide powder with purity of greater than or equal to 99.99%, apparent density of 0.28~0.3g/cm3. High-purity ultrafine WO3 has good catalytic performance for many reactions such as hydrodeoxygenation (HDO), oxidation, hydrocarbon isomerization and alkylation, etc. It is an important catalyst in petrochemical industry and has a very broad application prospect in the field of catalysis. WO3 also has good photochromic property and gas sensitivity. With the further development of material science, other…

Medium tungsten trioxide can be produced by ammonium paratungstate – sodium paratungstate complex salt method. The apparent density of the obtained tungsten trioxide is 0.8~1.0g/cm3. Producing Method Step one: Pour water into the complex salt to make into slurry and heat to boiling. Then, spray the slurry into 30%~31% concentrated hydrochloric acid solution which is simmering. The specific mass ratio: Complex salt: deionized water: hydrochloric acid = 1:0.36~0.38:1.06. It takes 0.5h or so in total reflux reaction under boiling. Step…

Coarse tungsten trioxide has an apparent density of 1.2~1.6g/cm3. Coarse WO3 has greater apparent density as its particle size is larger than fine tungsten trioxide of 0.5~0.7g/cm3. Producing Method The production of coarse WO3 is treating “ammonium paratungstate – sodium paratungstate complex salt” with saturated ammonium chloride solution, the specific steps are shown as follows: Add complex salt and saturated ammonium chloride solution with a solid-to-liquid ratio of 1: 5.5 in a reaction vessel equipped with a high speed stirrer.…

Fine tungsten trioxide can be prepared by double salt method with apparent density of 0.5~0.7g/cm3. Smaller the particle size, smaller the apparent density. Its specific production process is show as bellow: Mix double salt and water. And pour 30% to 31% concentration of cold hydrochloric acid slowly into the slurry. At the beginning, colloidal tungstic acid with white amorphous appearance is formed. The white tungstic acid turns into yellow tungstic acid precipitate with the continuous increase of the hydrochloric acid,…