Medical radiation-proof tungsten alloy screen is new type of protective screen that has excellent radiation shielding performance (which is better than that of lead screen) and is environmentally friendly, so it is expected to replace the traditional lead screen for use in CT rooms and dental hospitals.

X-ray protective tungsten alloy screen is made of high quality tungsten based alloy with excellent X-ray radiation shielding performance, which is mainly applied for enhancing the protective effect of patients’ radiology diagnosis and treatment. Also, such a screen can be used in industrial radiation protection.

Fabrication of cemented carbides is the main use of tungsten carbide (WC). This application uses powders with a wide range of mean particle size. Submicron grained cemented carbides use very tiny tungsten carbide powders, which is very useful as catalyst. Cemented carbides of submicron carbide grains show an improved toughness to hardness ratio.

Ammonium paratungstate (APT) as an important precursor in tungsten industry. It is the raw material for the majority of tungsten products. For example, tungsten trioxide (WO₃), tungsten blue oxide, tungstic acid and ammonium metatungstate, etc. These are all intermediates by subsequent calcination and/or reduction of APT. Another significant middle product is monoclinic W₁₈O₄₉, (WO_2.72), one of the tungsten suboxides, is an important intermediate product of WO₃, influencing significantly the morphology of the tungsten powder end-product. W₁₈O₄₉ crystallises in needles and agglomerates of needle-like crystallites. This is true for the formation by vapour transport, in oxidative, and reductive atmospheres and for the transformation in the solid phase.

WO3 composite coating is a good choice for formaldehyde degradation. It is the photocatalytic performance of tungsten trioxide that make WO3 composite coating have the performance of degrading formaldehyde, thereby improving air quality and human health.

Ammonium metatungstate is used as the active component in the preparation of honeycomb ceramic catalyst. And the prepared high specific surface area porous honeycomb ceramic catalyst is particularly suitable for soot purification in thermal power plants, glass plants, chemical plants and other fields.

This is a method of preparing ammonium paratungstate. This is just a general method for preparing ammonium paratungstate in the prior art.

How to prepare ammonium paratungstate by ion exchange method?

Ammonium paratungstate, APT for short, is an important inorganic salt product with chemical formula (NH4)10(H2W12O42) ·4H2O. There are many ways to prepare APT, including ion exchange method, neutralization method, solvent extraction method, ultrasonic method, two step ion exchange method, evaporation crystallization method, and tungstic acid method, etc. Wherein, ion exchange process is attracted much attention.

The researchers proposed a new two step ion exchange method for the preparation of high purity ammonium paratungstate. This method overcomes the shortcomings of low tungsten adsorption capacity, low concentration of crude sodium tungstate feed liquid, and large dilution of feed liquid in the ion exchange process using strong basic anion exchange resin, while maintaining certain advantages.