Thermo-kinetic studies of NaN3/KNO3 air bag gas generant mixture

Abstract

This paper addresses the thermal behavior of commonly used NaN3/KNO3 gas generant mixtures under different heating rates using simultaneous thermal analyzer. The thermal decomposition of the mixture was rigor under oxygen atmosphere with exothermic heat of reaction equivalent to 1.12 g of TNT. For the first time, the experimental investigation was carried out for the stoichiometric mixture of NaN3/KNO3 up to 1150 °C. It was identified that most of the gas release took place beyond 500 °C and decomposition ceased before 1150 °C. Thermo-kinetic parameters were also estimated for the DSC data. Spectroscopic studies performed on the mixture before and after combustion supplemented the reaction mechanism of decomposition. It was also evident that relatively complete combustions with elevated heat of liberations took place at higher heating rates. The thermal decomposition data of the mixture obtained from the experiments can be used for safe processing, storing, and transportation of the mixture in automotive sector.