Thermal hazard analysis and combustion characteristics of four imidazolium nitrate ionic liquids

Thermogravimetry and differential scanning calorimetry (DSC) were used to investigate the thermal stability of four nitrate-based ionic liquids. The variations of thermal behavior for different numbers or lengths of alkyl substituents for imidazolium cations were analyzed systematically. Long-term stability and operating temperature for 1.0% mass loss during 10 h (T0.01, 10 h) were estimated using model-free perdition methodologies. The results of T0.01, 10 h were predicted to be 78.73 and 81.59 °C for [Bim][NO3] and [Mim][NO3], respectively. The apparent activation energy (Ea) was obtained using four isoconversional methods at various heating rates through DSC experiments. This study confirmed that [Bim][NO3] and [Mim][NO3] decomposed swiftly, and the gaseous products can result in ignition and continuous combustion.