Ammonium Paratungstate Property
Ammonium paratungstate property determines its performance. APT structure affects the appearance, property of tungsten products. Its down-stream products follow the property, which means grain size, apparent density is related to APT. Besides that, APT contains different crystal water to produce ammonium tungsten bronze will have distinguish on property.
1.Ammonium paratungstate is white crystalline powder, it has flake or needle shape. 2.APT crystalline chemical formula is 5(NH4)2O•12WO3•nH2O(n=5,7,11), it is slightly soluble in water, solubility is less than 2% under 20℃. It will also increase with temperature. 3.It is insoluble in ethanol.
Ammonium paratungstate has thermal decomposition property, when heat to 220-280℃ will lose part of ammonium and crystal water and converts into ammonium metatungstate. When heat to 600℃ will lose all of ammonium and crystalline water and converts to tungsten trioxide completely.