Thermal decomposition of 4-amino-1,2,4-triazolium nitrate under infrared laser heating

The objective of this work is to study the behavior of an ionic liquid, 1-H-4-amino-1,2,4-triazolium nitrate, during thermal decomposition driven by an infrared laser (10.6 mu m). The focus was to understand the initial decomposition reactions and subsequent reactions that lead to ring decomposition and eventually to ignition. A triple quadrupole mass spectrometer with molecular beam sampling was used to obtain gaseous decomposition species of the sample. The principal mass peaks that may contain multiple masses were analyzed through tandem mass techniques. The experiments were conducted at a laser heat flux of 100 W/cm(2) in helium at 1 atm. To assist in interpreting the data, three other materials were also tested, 4-amino-1,2,4-triazolium hydrochloride, 4-amino-1,2,4-triazole, and 1-H-1,2,4-triazole. The results show that the most probable route to initiate the decomposition of the 1-H-4-amino-1,2,4-triazolium nitrate is through proton transfer from N-1 site to the nitrate forming a neutral pair, nitric acid and amino-triazole. Subsequent reactions involve decomposition of the neutral pair and their interactions. (c) 2007 Elsevier B.V. All rights reserved.