TNT decomposition

Their props were approximately as follows Ballistic Strength 126% TNT Brisance — less than for TNT Decomposition Temperature — 278°C Detonation Velocity — less than for EDD Impact Sensitivity —similar to that of EDD Reaction with Metals — similar to that with Amatols (See Vol 1 of Encycl, p A161-R)... 

The enthalpy ol formation of trinitrotoluene (TNT) is —67 kj-mol", and the density of TNT is 1.65 g-cm-3. In principle, it could be used as a rocker fuel, with the gases resulting from its decomposition streaming out of the rocket to give the required thrust. In practice, of course, it would be extremely dangerous as a fuel because it is sensitive to shock. Explore its potential as a rocket fuel by calculating its enthalpy density (enthalpy released per liter) for the reaction... 

C04-0139. Compounds that undergo explosions typically produce large quantities of hot gases from much smaller volumes of highly reactive solids or liquids. Balance the reaction for the decomposition of trinitrotoluene (TNT), a violent explosive C7 H5 N3 Og(/) N2(g) + C02(g) + H2 0(g) + C(,3 )... 

Silver perchlorate forms solid complexes with aniline, pyridine, toluene, benzene and many other aromatic hydrocarbons [1], A sample of the benzene complex exploded violently on crushing in a mortar. The ethanol complex also exploded similarly, and unspecified perchlorates dissolved in organic solvents were observed to explode [2], Solutions of the perchlorate in benzene are said to be dangerously explosive [3], but this may be in error for the solid benzene complex. The energy released on decomposition of the benzene complex has been calculated as 3.4 kJ/g, some 75% of that for TNT [4],... 

An 850 kg batch of a slightly doped form of azodicarbonamide exploded violently, with a TNT equivalence of 3.3 kg, 5 minutes after sampling at the end of drying. The probable initial temperature was 65°C, the lowest self accelerating decomposition temperature 90°C, and such decomposition is not explosive. Full explosibility tests, including detonability, had shown no hazard. Further study demonstrated that slightly contained azodicarboxamide, thermally initiated at the bottom of a column or conical vessel could explode even at the 5 kg scale. The above TNT equivalence corresponds to decomposition of 4% of the available charge. The cause of the presumptive hot spot is unknown. 

Sodium carbonate was added to a heated tank of washed TNT to neutralise excess acidity. It is known that the assym. isomer of TNT reacts with sodium carbonate to form unstable compounds, and decomposition led to a fire and detonation of 5 tonnes of explosive. 

In general, C-nitro compounds are more stable than /V-nitro compounds because of the higher bonding energies in the former type. Evidence is offered [1] that decomposition and explosion of many nitro-derivatives proceeds through the aci-form, and that sensitivity corresponds to the proportion of that present. In terms of this work, sensitisation by very small proportions of soluble organic bases is most important this is not limited to nitroalkanes. TNT can apparently be brought to the sensitivity of lead azide by this means. For a physicist s view of this sensitisation,... 

VJ Both Sandia and FOI analyzed the decomposition products of TNT in various soils and conditions. An example of a FOI result is shown in Figure 8.4. 

These are products extracted out of soil contaminated with TNT, RDX, and TETRYL (Trimtrophcnyl-M-mcthyInitramine). For TNT a decomposition product that had a longer half-life in the soil was 4-amino-dinitrotoluene, so in doing area reduction one should include this product. 

Temperature increase can cause various physical and chemical processes for the adsorbed TNT molecules, including melting, vaporization, and decomposition. All these reactions are endothermic except deflagration. Since the resonance frequency of the cantilever returns to its original value after deflagration, it can be assumed that all the adsorbed TNT desorbed from the surface. 

Note These compounds readily undergo explosive decomposition when sufficient ignition stimulus is applied. shock stimulus is frequently needed to activate the nonionic organic molecules (e.g., TNT) these compounds will frequently merely burn if a flame is applied. 

Cook (Ref 1), in describing thermal decomposition of some HE s conducted in the quartz spring apparatus (described in Ref 1, p 175 and shown there in Figs 8.1a 8.1b), stated that PETN, RDX, Tetryl and to a small extent TNT decomposed autocatalyti-cally. EDNA followed the first-order decomposition law only until about 5% of the explosive had decomposed and then the reaction stabilized. The term autostabilization was applied here on the supposition that one of the condensed decomposition products of EDNA which accumulated in the explosive apparently tended to stabilize the bulk of expl and thus slow down the decomposition. After about 10% of the expl had decompd, however, the "autocatalysis developed. 

The curves logw vs time are given on pp 176-77 for AN, EDNA PETN. This method is not applicable to expls in which.weight loss is the result solely of decomposition and not merely of vaporization or both vaporization and decomposition. It cannot be used for TNT because at the temperatures at which. it. could be applied vaporization and decomposition take place simultaneously... 

Recently Lee et al (Ref 3) re-examined the behavior of PETN under 10 to 50 kbars of external pressure. They also find a reduction in decomposition rate with increasing applied pressure. HMX behaves similarly to PETN. TNT whose explosion products contain a high proportion of solid carbon, as expected from LeChatelier s Principle, shows little pressure effect on its thermal decomposition. Nitro-methane, however, appears to decompose more rapidly under an external pressure of 50 kbars than 10 kbars. This effect is not completely understood but Lee et al suggest that high pressure may favor the formation of the thermally less stable aci form of Nitromethane ... 

This mixt is more powerful than TNT or Tetranitroaniline, but is insensitive to shock or friction and burns without detonation when dropped in a red hot crucible or ignited by flame. Its ignition temp is 194-208°. It cannot be stored for longer than 24-48 hours, as bubbles, resulting from decomposition of the H2 02, are evolved and the mass hardens. Moreover its explosive power decreased after 48 hours of standing (Ref 1)... 

TNT begins to decompose at 150° and on long heating at constant temperature, the explosion temperature is raised by the formation of decomposition products... 

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