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.

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.

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.

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