Ammonium metatungstate, AMT for short, a kind of white crystallized powder, is mainly applied for petroleum industry. And it can also be used in the manufacture of various petrochemical catalysts and other tungsten compounds. Its molecular formula is (NH4) 6H2W12O40 ? XH2O.
AMT is usually used as one of the precursors of tungsten carbide (WC) catalyst, and the properties of AMT precursor affect the morphology and size distribution of WC microsphere, which have a finally effect on the catalyst activity.
How to prepare AMT?
1. Heat the APT to make it lose part of the ammonium and water of crystallization, changing into AMT, which is easily soluble in water, and then by evaporation crystallization.
2. Adopt ammonium tungstate or sodium tungstate solution as raw material, use solvent extraction or ion exchange method to obtain AMT solution, and then by evaporation.
3. Stir ammonium paratungstate (APT) in water, use acid to neutralize the solution to PH3-4, so that APT solution can change into AMT solution, and then evaporate.
FSSS: 32-48u.
Scott: 1.8-2.4g/cm3.
Mesh: -80.
More details, please visit:
http://www.tungsten-powder.com/ammonium-metatungstate-hydrate.html
