Thermal transformations of aluminium nitrate hydrate

By means of the thermogravimetric (TG) method, and differential thermal analysis (DTA) with simultaneous chemical analysis of the gaseous reaction products, X-ray diffraction phase analysis, and infrared spectroscopy, stages of decomposition of Al(NO3)3·9H2O were studied. It has been found that the thermal decomposition of Al(NO3)3·9H2O proceeds in a few stages. First stage is connected with partial dehydration of the compound without decomposition of the nitrate groups. The successive stages comprise the hydrolytic processes, which are connected with further dehydration and loss of the nitrate groups. The process proceeds with the formation of amorphous alumina.