Ammonium metatungstate (AMT) is a white crystal powder or yellowish crystal powder with good water solubility, which can be used for preparation of diesel hydrogenation catalyst. For example, the researchers have proposed a method for preparing FCC diesel hydrorefining catalyst by using ammonium metatungstate as an active component.

How to prepare ammonium metatungstate crystal? Or how to prepare AMT crystal? There are various preparation methods, such as thermal decomposition method, neutralization method, solvent extraction method, tungstic acid method, ion exchange method, etc.

Ammonium metatungstate (AMT) is a white or light yellow crystalline salt that is soluble in water. Generally, ammonium metatungstate solubility refers to the solubility of AMT in water. The data shows that at 20 °C, the solubility of AMT in water is 303.9g, and its solubility increases with increasing temperature. Besides, the aqueous solution of AMT is quite stable.

How to prepare high purity ammonium metatungstate crystal? The researchers proposed a method for preparing high-purity AMT crystals - neutralization-nanofiltration coupling process. This method can not only obtain a high concentration AMT solution to reduce the cost for the subsequent crystallization process, but prepare AMT with less impurity content to ensure the preparation of high purity ammonium metatungstate.