IDENTIFICATION OF THE THERMAL-DECOMPOSITION BEHAVIOR OF AMMONIUM PENTABORATE

The thermal decomposition behaviour of ammonium pentaborate octahydrat e (APB) and its conversion to boron oxide were investigated using isot hermal thermogravimetry, non-isothermal thermogravimetry and different ial thermal analysis. TG and DTA curves of APB were obtained in its ow n decomposition atmosphere. According to these curves, the thermal dec omposition of APB to boron oxide occurs in two main steps: the first s tep corresponds to the dehydration and the second is attributed to the deamination. It was found that the shapes of the TG curves recorded u nder isothermal conditions at different temperatures are strongly affe cted by the working temperature. Also, two endothermic peaks were obse rved on the DTA curve of APB, representing dehydration and deamination processes, respectively.