Ammonium metatungstate water-soluble white crystalline powder or slightly yellow. Ammonium metatungstate is used in the manufacture of tungsten metal, alloy steel, fireproof fabrics, etc. It is also used in the ceramic industry.
Chinese name of Ammonium metatungstate
Ammonium metatungstate
Chinese alias of Ammonium metatungstate
Ammonium metatungstate hydrate, in addition, ammonium metatungstate has several aliases, including but not limited to:
Ammonium metatungstate hydrate
Decammonium dodecatungstate
Sodium (T-4)-tungstate
Ammonium metatungstate hexahydrate
Ammonium paratungstate hexahydrate
Ammonium metatungstate hexahydrate
Ammonium tungsten oxide pentahydrate
In addition to the above aliases, ammonium tungsten oxide and ammonium metatungstate liquid are also the names sometimes used, of course, if tungsten in simplified Chinese character is replaced by “tungsten” in traditional Chinese character commonly used in Hong Kong, Macao and Taiwan, it is also the name of ammonium metatungstate.
English Name of Ammonium Metatungstate (Foreign Name)
Ammonium Metatungstate
Abbreviation of Ammonium Metatungstate in English (foreign name)
AMT
English Synonyms of Ammonium Metatungstate
Ammonium Metatungstate Hydrate
CAS number of Ammonium Metatungstate Hydrate
Ammonium metatungstate has more than one CAS number, this is due to its existence in different forms or purity, common CAS numbers include:
12333-11-8, 11120-25-5, 14311-52-5
Molecular formula of Ammonium metatungstate
The molecular formula of ammonium metatungstate has two common forms: H28N6O41W12 and (NH4)6H2W12O40-XH2O (where X represents the amount of water of crystallization).
Molecular weight of ammonium metatungstate
2974.32000
The above figures are calculated based on the molecular formula of ammonium metatungstate H28N6O41W12
Exact mass of ammonium metatungstate
2975.44000
The exact mass of ammonium metatungstate is a key chemical parameter that provides the sum of the exact masses of all the atoms in the molecule, and the exact mass of ammonium metatungstate is approximately 2975.44000. This exact mass value is based on the molecular formula of ammonium metatungstate, H28N6O41W12, which takes into account the exact atomic masses of the various elements and their numbers in the molecule as well as the effect of the isotopic distribution on the total mass. on the total mass. Knowledge of the exact mass of Ammonium Metatungstate helps to control and optimize the relevant processes more accurately.
PSA of Ammonium Metatungstate
603.47000
PSA (Polar Surface Area) is an important physicochemical parameter of ammonium metatungstate, which reflects the sum of the surface areas of the polar atoms in the molecule and is important for understanding the reactivity and biological activity of the molecule. The PSA value of ammonium metatungstate is about 603.47000.This value is calculated based on the molecular structure and atomic composition of ammonium metatungstate. In the ammonium metatungstate molecule, oxygen atoms are the main polar atoms, which form chemical bonds with tungsten atoms and ammonium ions, thus contributing a large polar surface area.
Properties of Ammonium Metatungstate
Ammonium metatungstate water-soluble white crystalline powder or slightly yellow. Ammonium metatungstate is soluble in water and ammonium secatungstate is slightly soluble in water, which is the obvious difference between ammonium metatungstate and ammonium secatungstate.
The use of ammonium metatungstate
Ammonium metatungstate has a wide range of industrial and technical applications. The main uses of ammonium metatungstate include metallic tungsten powder, tungsten compounds, tungstate, tungsten oxides, petrochemical catalysts, refinery catalysts, tungsten-based catalysts, catalytic cracking, hydrodesulfurization, ceramic raw materials, special ceramics, alloy steel additives, fireproofing textile treatments, nuclear shielding materials, corrosion inhibitors and so on.
Specification Standard of Ammonium Metatungstate (Chinatungsten)
Grade of Ammonium Metatungstate (China National Standard)
Basic specifications for the supply of ammonium metatungstate (Chinatungsten)
Production Process of Ammonium Metatungstate
There are many methods to produce AMT, and the basic process flow and principle of the main production methods are:
- Using ammonium tungstate solution as raw material, solvent extraction or ion exchange method is used to produce ammonium metatungstate by solution, and then ammonium metatungstate is obtained by evaporation and crystallization;
- Solvent extraction method with sodium tungstate solution as raw material to get AMT solution, and then get ammonium metatungstate by evaporation and crystallization;
- Heat thermal dissociation of APT, so that it loses part of the ammonium and water of crystallization, transformed into ammonium metatungstate which is soluble in water, and then get ammonium metatungstate by evaporation and crystallization;
- Neutralize APT with acid under stirring in water to PH3-4 so that APT is converted into AMT solution, and then get ammonium metatungstate by evaporation and crystallization.
Ammonium metatungstate production method-neutralization method
Neutralization method takes ammonium sec-metatungstate and nitric acid as raw materials to prepare ammonium metatungstate: add ammonium sec-metatungstate to deionized water and ammonium citrate to form a slurry containing WO312%-30% concentration. According to ammonium paratungstate: nitric acid = 1:20 to add 3% to 5% of dilute nitric acid to ammonium paratungstate slurry, control the solid-liquid ratio of 1: (3 ~ 4), Ph value of 2 ~ 4, heating to dissolve, so that the relative density of the solution up to 1.18 ~ 1.20, heated to 80 ~ 90 ℃, constant temperature and constant volume control of the value of Ph, stirring reaction for 4h, aging for a few hours, the liquid is concentrated to the content of WO3 in the 50 percent or so, filtering! Remove insoluble material, the clear liquid continue to concentrate, cooling crystallization, to 80 ℃ drying system.
Ammonium metatungstate production method – tungstic acid method
Tungstic acid method will be tungstic acid dissolved in ammonia, add containing boiling deionized water, heating under stirring by ammonia, so that Ph = 8, in the case of boiling solution add acetic acid, and then dilute nitric acid to adjust the Ph value of 2 ~ 4, continue to heat and concentrate to the relative density of 1.5 ~ 2, stop heating, cooling and filtration. The filtrate is added ethanol and stirred thoroughly, filtered after settling, and the crystals are dried and crushed at 80℃ to obtain the product.
Ammonium metatungstate production method – thermal decomposition method
Thermal decomposition method uses ammonium paratungstate as raw material for the preparation of ammonium metatungstate: after mixing ammonium paratungstate and a small amount of citric acid catalyst, put it into the far-infrared rotary furnace, control the thermal decomposition temperature of 200～280℃, and decompose it for about 1 h. At this time, some ammonia and water are removed. At this time, some ammonia and water are removed, and the weight loss rate of ammonium paratungstate is 5% to 6%. After the thermal decomposition of the product immediately into a slurry, add appropriate amount of ammonia, adjust the Ph value in the range of 3 ~ 4, at 90 ℃ to cook the slurry. After evaporation and concentration to the ammonium metatungstate content of 50% can be sold as liquid products, when evaporation and concentration to the original volume of 20% crystallization, filtration and separation, granulation products. The evaporation concentrate can also be spray-dried to produce products. Such as 45% ~ 50% ammonium tungstate through the high-speed centrifugal rotary spray dryer, the inlet hot air temperature of 250 ~ 300 ℃, out of the tower temperature of 90 ~ 95 ℃, the product obtained for the spherical crystals, particle size of 200 mesh accounted for 95%, containing free water <1.5%.
Ammonium metatungstate production method-solvent extraction method
Solvent extraction method will be ammonium tungstate solution with organic extractant di-(2-ethylhexyl) phosphate (D2EHPA) or tri-butyl phosphate (TBP) and kerosene solvent composition of the organic phase, the extraction of ammonium ions in ammonium tungstate, so that the Ph value is reduced to 2 ~ 4, after boiling to generate ammonium metatungstate solution. Concentration and crystallization, filtration and separation, drying to produce products.
Ammonium metatungstate production method-ion exchange method
Ion exchange method takes ammonium paratungstate as raw material, and ammonium metatungstate is prepared by ion exchange method: heating ammonium paratungstate at 130～140℃ for 1～8 h, adjusting the generated material into slurry, and boiling at 80～100℃ for 2～6 h to generate ammonium metatungstate solution. Then it is concentrated and crystallized, filtered and separated, and dried to obtain the product. The electrodialysis method uses ammonium tungstate or ammonium sec-tungstate as raw material to prepare ammonium metatungstate by electrodialysis: ammonium sec-tungstate is added to the anode chamber, when the current passes through, ammonium ions enter into the cathode chamber through the anion-exchange membrane, and the concentration of ammonium metatungstate in the anode chamber increases. Finally, ammonium metatungstate solution is released from the cathode chamber, and ammonium metatungstate is produced by processing according to the above method.
Packing of ammonium metatungstate
Inner double-layer plastic outer iron drum, net weight 25kg or 50kg per drum.
Inner double-layer plastic outer paper drum, net weight 25kg or 50kg per drum.
Aluminum foil sealed bag, 1, 2, 5 kg per bag.
Plastic bottle, glass package, 1kg per bottle.
Sample package, according to the quantity and customer’s demand
Manufacturers and Suppliers of Ammonium Metatungstate
CTIA GROUP LTD and its parent company have been in the tungsten products industry for a long time for nearly 30 years, specializing in flexible customized global services for tungsten and molybdenum products. CTIA GROUP LTD can customize and process all kinds of Ammonium Metatungstate according to customers’ requirements in terms of specifications, performance, status and specification standards and packaging.
