(173d) Evaluation of the Thermal Decomposition Products of 2-Nitrotoluene

The run-away reaction potential of 2-nitrotoluene is a threat to the chemical process industry, due to its unstable structure and extensive heat release during upset situations. Though some experimental has been made to understanding the macroscopic properties of 2-nitrotoluene, much work remains to be done to fundamentally understand its microscopic mechanism. In this work, the thermal decomposition reaction mechanism of 2-nitrotoluene was studied by automatic pressure tracking adiabatic calorimeter (APTAC) measurements and gas chromatography-mass spectrometry (GC-MS) analysis. Experimental parameters and results such as detected ‘onset’ temperature, pressure increase rate, temperature increase rate and maximum temperature are present. Two distinct initial decomposition steps were identified through the decomposition products in the liquid phase resolved from GC-MS measurements.

This study employs the APTAC to study the effects of various common contaminants on 2-nitrotoluene thermal decomposition, including sodium sulfate, sodium chloride, potassium carbonate and potassium chloride. Sodium sulfate and potassium chloride will increase the onset temperature about 20 °C, while the potassium carbonate can lower the detected onset temperature about 20 °C. Sodium chloride will not influence the stability of the 2-nitrotoluene’s thermal stability. Fundamental understanding of the initial thermal decomposition permits a better hazard analysis this material.