Explosives 3,5-dinitrotoluene

Table 4 gives details of some relevant physical and thermal properties of a range of common explosives that have been encountered in terrorist bombs. It should be noted that DMNB (2,3-dimethyl-2,3-dinitrobutane) is one of the taggants added to plastic explosives under the Montreal Convention on marking of plastic explosives. Dinitrotoluenes are frequently added to blasting gelatine as a minor component and are also found in TNT as a significant impurity. 

Mixtures of HNO, H2SO4, and SO also result in high concentrations of NO/, and toluene can be readily nitrated at —40 to — 10°C as a result (6). At these low temperatures, the formation of the meta-isomer of mononitrotoluene (MNT) is greatiy reduced. Such a reduction is highly desired in the production both of dinitrotoluenes (DNTs) employed to produce intermediates for polyurethane production and of trinitrotoluene (TNT), which is a high explosive. > -MNT results in the production of undesired DNT and TNT isomers (see Nitrobenzene and nitrotoluenes). 

Organic Reactions. Nitric acid is used extensively ia iadustry to nitrate aHphatic and aromatic compounds (21). In many iastances nitration requires the use of sulfuric acid as a dehydrating agent or catalyst the extent of nitration achieved depends on the concentration of nitric and sulfuric acids used. This is of iadustrial importance ia the manufacture of nitrobenzene and dinitrotoluene, which are iatermediates ia the manufacture of polyurethanes. Trinitrotoluene (TNT) is an explosive. Various isomers of mononitrotoluene are used to make optical brighteners, herbicides (qv), and iasecticides. Such nitrations are generally attributed to the presence of the nitronium ion, NO2, the concentration of which iacreases with acid strength (see Nitration). 

Dinitrotoluene [602-01-7] M 182.1, m 63 . Distd in steam and crystd from water or benzene/pet ether. Stored with 10% water. Could be EXPLOSIVE when dry. 

If unstable chemicals have to be kept hot, the heating medium should be incapable of overheating them. Some acidic dinitrotoluene should have been kept at 150°C, as it decomposes at higher temperatures. It was heated by steam at 210°C for ten days in a closed pipeline and decomposed explosively [10]. 

Figure 15.14 Separation of explosives exnacted from water by using SPE-SFE-GC at several SEE trapping temperatures, peak identification is as follows NG, nitroglycerin 2,6-DNT, 2,6-dinitrotoluene 2,4-DNT, 2,4-dinitrotoluene TNT, triniti otoluene IS, 1,3-tiichloroben-zene. Adapted Journal of High Resolution Chromatography, 16, G. C. Slack et al., Coupled solid phase extraction supercritical fluid extraction-on-line gas cliromatography of explosives from water , pp. 473-478, 1993, with permission from Wiley-VCH.

Trinitrotoluene TNT is a well-known explosive obtained hy further nitration of the dinitrotoluenes. 

Addition of sodium azide to a solution of the acid in 20% oleum at 5-10°C to produce 3-amino-2,5-dinitrotoluene must be slow (0.1 g portions dining 1 h) to avoid explosion. 

A series of mixtures of nitric acid with one or more of mono- and di-nitrobenzenes, di- and tri-nitrotoluenes have been shown to possess high-explosive properties [1]. Critical detonation diameters for mixtures of nitric acid with dinitrotoluene and TNT have been determined [2],... 

The effect of sulphuric acid and oleum on the explosive properties of nitromethane, dinitrotoluene, trinitrobenzene and trinitrotoluene was studied. They are considerably sensitised. 

Mixtures with nitrobenzene were formerly used as liquid high explosives, with addition of carbon disulfide to lower the freezing point, but high sensitivity to mechanical stimulus was disadvantageous [1], Dining the recovery of acids from nitration of toluene, mixtures of the oxide with nitrotoluene or dinitrotoluene may... 

To explore the capability of OFRR-based pGC in explosive detection, 2,4-dinitrotoluene (DNT) is chosen as a model system, due to its chemical structure... 

The 60 still base was a 45.5 m3 horizontal, cylindrical, mild steel tank 7.9 m long and 2.7 m diameter. The still was used to separate a mixture of the isomers of mononitrotoluene (MNT), two of which (o-nitrotoluene and m-nitrotoluene) are liquids at room temperature and third (p-nitrotoluene) a solid. Other byproducts were also present, principally dinitrotoluene and nitrocresols. It is well known in the industry that these nitro compounds can be explosive in the presence of strong alkali or strong acid, but in addition explosions can be triggered if they are heated to high temperatures or held at moderate temperatures for a long period. 

Solid-phase microextraction (SPME) for preconcentration, followed by GC/ Ion Trap MS, was used for trace analysis of explosives and their metabolites in seawater [9]. NICI was used with methane as reagent gas. Compounds of interest included RDX, TNT and two of its metabofrtes 2-amino-4,6-dinitrotoluene (2ADNT) and 4-amino-2,6-dinitrotoluene (4ADNT). Although the instrument sensitivity was in low-ppb range, the detection limits for SPME with GC/ITMS... 

Electron-transfer-induced FQ is the most practical and efficient mechanism of signal transduction for the detection of explosives. This is because explosives, especially 2,4,6-trinitrotoluene (TNT), are often highly electron-deficient molecules that readily accept electrons from excited fluorophores. In addition, explosive devices that contain TNT also usually contain a synthetic by-product, 2,4-dinitrotoluene (DNT), which is also highly electron deficient. A basic frontier molecular orbital-based mechanism for electron transfer FQ is illustrated in Figure 3. 

More complex explosives incorporating amino groups have been prepared from the reaction of polynitroarylene halides with amine nucleophiles. Agrawal and co-workers have synthesized PADNT (107) from the reaction of 4-amino-2,6-dinitrotoluene (46) with picryl chloride (87) in methanol 4-amino-2,6-dinitrotoluene is synthesized from the reduction of... 

Two other derivatives of toluene are the important explosive trinitrotoluene (TNT) and the polyurethane monomer toluene diisocyanate (TDI). TNT requires complete nitration of toluene. TDI is derived from a mixture of dinitrotoluenes (usually 80% o,p and 20% o,o) by reduction to the diamine and reaction with phosgene to the diisocyanate. TDI is made into flexible foam polyurethanes for cushioning in furniture (35%), transportation (25%), carpet underlay (20%), and bedding (10%). A small amount is used in polyurethane coatings, rigid foams, and elastomers. 

During World War II, copious quantities of ordnance were lost into the harbor at Halifax, Nova Scotia. Decades later, these UUXO now present a significant environmental contamination problem. Studies conducted on this ordnance by Sandia National Laboratories [1] suggest that there may be sufficient concentrations of explosive chemical signature compounds emanating from UUXO to enable detection with chemical sensors. Some UUXO in Halifax Harbor have been shown to produce parts-per-billion levels of explosives in the water near the ordnance. In addition to the parent explosive compound (TNT), other explosive-related compounds such as 2,4-dinitrotoluene (2,4-DNT) were detected, as were degradation products of TNT such as 4-amino-2,6-dinitrotoluene (4-ADNT), and... 

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