Non-isothermal decomposition kinetics of pyridinium nitrate under nitrogen atmosphere

Abstract

The thermal stability and decomposition kinetics of the ionic liquid pyridinium nitrate was investigated by non-isothermal thermogravimetric analysis in an inert atmosphere (nitrogen). For the kinetic experiments, the thermal behavior of the sample was studied in the temperature interval from 360 up to 600 K at different heating rates (5, 10, 15 and 20 K/min).The kinetic parameters of decomposition including activation energy and pre-exponential factor under nitrogen atmosphere were evaluated by menace of two model-free methods – Friedman and Kissinger-Akahira-Sunose. Depending on the used calculation model, the obtained activation energy and pre-exponential factor values with respect to the degree of sample conversion during the kinetic experiment for method ranged in the intervals of 76.36–112.56 kJ/mol and 1.72×105–1.42×1010 min–1, respectively. Based on the attained kinetic parameter values it was established that the process of pyridinium nitrate decomposition occurred as a first-order reaction. Considering the calculated kinetic parameters, a decomposition mechanism for pyridinium nitrate was proposed.