99.5% tungstic acid may be prepared by “dissociation-slurrying-acid decomposition” process. This process uses less raw materials and auxiliary materials. And it is easy to operate. So, it is cost-saving and time-saving. Some people have conducted experiments on acid decomposition of tungstic acid, acid decomposition of ammonium paratungstate (APT), and acid decomposition of CaWO4 to make tungstic acid. The first two methods have been found to be slow to decompose. As the decomposition reaction proceeds, the acidity decreases continuously, so that…

Fe-doped tungstic acid may be prepared using sodium tungstate and iron salts as materials. Since Fe initiates the Fenton reaction, the photocatalytic activity of tungstic acid is greatly improved. Also, this is a heterogeneous reaction that avoids the loss of iron ions and thus enables the reuse of the catalyst. Tungsten compounds have a wide range of applications in the field of photocatalysis. These compounds can undergo intramolecular charge transfer under the irradiation of ultraviolet light, thereby triggering the degradation…

Industrial grade tungstic acid is an intermediate compound of ammonium paratungstate (APT) in powder metallurgy. Preparation of Industrial Grade Tungstic Acid Step 1: Add tungstic acid raw material with a purity of 99.95% into the inorganic acid solution, the mass ratio of the inorganic acid solution to the tungstic acid raw material is 1:1 to 2:1, ultrasonic irradiation oscillation for 3h-6h. The temperature is controlled at the range of 20°C~40°C, suction filtration to obtain filter cake solid; Step 2: Put…

High-purity tungstic acid is a new chemical material with a wide range of application prospects, which may be prepared by a new process of dissociation – slurrying – acid decomposition, with purity higher than 99.99% and average particle size of 0.61μm. The process is stable and easy to operate with high transformation rate. Tungstic acid may be produced by acid decomposition scheelite concentrate method, ammonium paratungstate method, artificial scheelite method, ammonium paratungstate sodium method, and the method of acid decomposition…

Nano grain size tungstic acid may be synthesized by chemical precipitation method using ammonium metatungstate (AMT) and hydrochloric acid (HCL) as raw materials, and the agglomeration of nanoparticles may be effectively improved with the addition of ethanol. And nano tungstic acid with high purity, small particle size and good dispersion may be prepared by liquid phase precipitation method in the alcohol-water system. Synthesis of Monodisperse Tungstic Acid Nanoparticles by UV Irradiation Monodisperse tungstic acid nanoparticles with an average particle size…

Yellow tungstic acid is the most common seen tungstic acid that appears as a kind of light yellow powder or crystalline with a melting point of 1473°C. It can not easily dissolve in phosphorus acid when it is fresh produced. It is insoluble in water. And it will be colloidizing after dipping so that it is soluble in ammonia solution, alkali solution and high concentrate hydrochloric acid. Its content will be different along with the changes of producing conditions. When…

White tungstic acid is one of different types of tungstic acid, showing the appearance of white crystalline powder. It is less active than microcrystalline structure white tungstic acid. However, it is active, optical sensitive and can be easy reduced. Its chemical formula is mWO3•nH2O. There is powder and colloform, and the latter is difficult to be prepared. Producing Methods 1. Can be produced by adding dilute nitric acid into sodium tungstate solution. 2. Decompose peroxide tungstate solution by nitric acid.…

Tungstic acid is a kind of yellow powder with the relative density of 5.5. It refers to hydrated forms of tungsten trioxide (WO3). The simplest form, the monohydrate, is WO3•H2O, the dihydrate WO3•2H2O is also known. Its boiling point is 1473°C. It is slightly soluble in hot water, slowly soluble in caustic alkali, and soluble in hydrofluoric acid (HF) and ammonia. While it is almost insoluble in acid, except HF. Tungstic acid can exist in a variety of states, including…

Metatungstic acid is a highly soluble and colorless crystal with a density of 3.93g/cm3. It is a kind of polytungstic acid with the formula H6 [H2 (W3O10) 4] • nH2O, in which n is 10 or 23. It decomposes at 50°C. Its solubility is 88.57g/100cm3 (in water, at the temperature of 25°C). Metatungstic acid can be made from the salt of metatungstic acid (metatungstate). Metoplutamate is an important industrial product developed in the late 1970s. It is mainly used as…