Study of Thermal Decomposition of Ammonium Paratungstate

Thermal decomposition of ammonium paratungstate 5[(NH4)2O] 12WO3.4H2O has been studied by differential scanning calorimetry and thermogravimetry. The results suggest that the water is lost in two steps at the temperature region 318.7 - 441.3 K, while anhydrous ammonium paratungstate is converted in to WO3 in the next three steps in the temperature region 441.3 – 767 K. The phases have been characterized by IR spectroscopy, elemental analysis and...