Thermokinetic Investigation of o-Nitrotoluene Using Reaction Calorimetry

Abstract

O-nitrotoluene (2-NT) is an important chemical widely used in the chemical industry. However, in the past 25 years, severe incidents have killed 10 people and injured more than 200 due to its thermal decomposition. This research focus on the thermal behavior of 2-NT decomposition. Advance Reactive System Screening Tool (ARSST) and the Automatic Pressure Tracking Adiabatic Calorimeter (APTAC) have been used to better understand the mechanisms that result in the explosion hazard of 2-NT. Key parameters such as observed onset temperature, onset pressure, self-heat rate, and pressure rate have been reported. Furthermore, the APTAC data is used in the calculation of Arrhenius data, reaction order, and self accelerating decomposition temperature (SADT). The results show that the 2-NT decomposition reaction has potentially severe consequences and is sensitive to the conditions like sample size and initial pressure. Also, there are two peaks in self-heat rate profile in the ARSST tests which indicate a minimum two different reactions that may be occurring during the decomposition. This study also focuses on the kinetics of the decomposition reaction which is nearly zero-order reaction and SADT prediction of the 2- NT of UN 25 kg package storage.