Study of the Heat and Kinetics of Nitration of 1,2,4‐Triazol‐5‐one (TO)

Abstract

The heat effects of the nitration and dissolution processes of 1,2,4‐triazol‐5‐one (TO) in acidic environments were measured by differential reaction calorimetry. The kinetics of nitration of TO in a 200‐mL reactor were investigated by UV/Vis spectroscopy. Temperature changes were measured in a 10‐L batch reactor during the TO nitration. A model of kinetics for the synthesis of 3‐nitro‐1,2,4‐triazol‐5‐one (NTO) was proposed and it was used to simulate the phenomena occurring in the calorimeter and in the reactors. The experimental data were compared with modeling results and parameters of the Arrhenius equation for synthesis of NTO with selected nitration mixtures were determined.

Empirical Kinetics Equation of the Synthesis of NTO in Nitric Acid

“…the reaction order of TO is 1. Accordingly,i ti sp roved to be suitable that the reactiono rder of TO is assumed as 1a sp roposed in the literature [1,[10][11][12][13].…”

“…The kinetic parameters of apparent activation energy [15] and frequency factor for TO nitration are assumed to be constant and independent on the HNO 3 concentration and the reactiono rder was not assumed as 1f or TO in advance, which is different from earlier reports [1,[10][11][12][13].I f the reactionr atesc alculated using the proposede quation are in agreement with the real values determined,i .e. macroscopic phenomena, it suggestst hat constant activation energy and frequency factor are reasonable.…”

“…Ap urely theoretical study was performedi nR ef.[1] and the studies connecting theories with the phenomena accompanying the nitration process of TO in laboratory and large-laboratory scales were conducted in Refs. [10][11][12][13].H erein, it is focusedo nt he nitration reaction of TO in nitric acid solutiona ss hown in Scheme 1, and the aim is to examine the influence of reaction conditions such as reaction temperature and concentration of reactants (HNO 3 and TO) on the nitration rate via an empiricalk ineticse quation [14].A ne xponential kinetic equation is set up by experimental data of the nitrationo fT Oi nH NO 3 with concentrations in the range 60.4-76.2 %. Additionally,t he experimental and calculated reactionr ates at HNO 3 concentrations in the 60.0-96.7 %r ange were determinedt ov erify the proposed model.The kinetic parameters of apparent activation energy [15] and frequency factor for TO nitration are assumed to be constant and independent on the HNO 3 concentration and the reactiono rder was not assumed as 1f or TO in advance, which is different from earlier reports [1,[10][11][12][13]].…”

A Study of the Detonation Properties, Propellant Impulses, Impact Sensitivities and Synthesis of Nitrated ANTA and NTO Derivatives

“…A similar strategy might work for the synthesis of 5-nitrimino-3-nitro-1,2,4-triazole (Scheme 4). When NTO is dissolved in concentrated nitric acid reactive by-products are formed [3,28]. If ANTA is mixed with concentrated nitric acid similar reactions might occur and the proposed route for 5-nitrimino-3-nitro-1,2,4-triazole (Scheme 4) would need to be modified.…”

Covalent and Ionic Insensitive High‐Explosives

“…Further research into the nitration of TO was undertaken by Trzciń ski et al [44].T he authors investigated the heat of reactiono fT On itration using ad ifferential reactionc alorimeter. The averageh eat of reaction value for the nitration of TO using various nitration mixtures was determined ( In 1990, Boyer et al reported the synthesis of the insensitive explosive4 ,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowurtzitane (TEX), which is synthesizedb yt he base catalyzed formation of 1,4-diformyl-2,3,5,6-tetrahydroxypiperazine (DFTHP)f ollowed by condensation of trimeric glyoxal with DFTHP in acidic solutiona nd subsequentn itration (Scheme 3) [46].…”