Effects of Ozone on the thermal decomposition behavior of Guanidine Nitrate

Abstract

The deterioration of chemicals contained in safety devices is an important issue because such devices must be ready for emergencies and should remain functional for a long period of time, even when exposed to degrading environments. In this study, we focused on the influence of ozone disinfection on chemicals present in safety devices as ozone can be used for virus inactivation in compartments housing these devices. Specifically, we conducted accelerated deterioration tests to evaluate the effects of ozone exposure on guanidine nitrate (GN).
Under the experimental conditions of this study, ozone-containing water deteriorated GN, whereas no change was observed in GN exposed to dry ozone. The ion chromatography (IC) analysis of the deteriorated product suggested that GN decomposed into nitrate ions, while capillary electrophoresis (CE) revealed a transformation of guanidine ions into ammonium ions. These results imply that GN deterioration produces ammonium nitrate. Additionally, ultraviolet-visible spectroscopy revealed the reaction products between GN and ozone, which were considered electrically neutral because of their absence in the results of IC and CE analyses.
In a differential accelerating rate calorimeter, decomposition started at a lower temperature for the deteriorated GN than for the pristine sample. This indicates that the deterioration products affected the thermal decomposition behavior of GN. This change in exothermic and pressure-release behavior is considered to have an impact on the performance of pyrotechnics using GN.