commonly known as TNT, is a constituent of many explosives, such as amatol, pentolite, tetrytol, torpex, tritonal, picratol, ednatol,
and composition B. It has been used under such names as Triton, Trotyl, Trilite, Trinol, and Tritolo.
It was first prepared in 1863 by German chemist Joseph Wilbrand and originally used as a yellow dye. Its potential as an explosive was not appreciated for several years mainly because it was so difficult to detonate and because it was less powerful than alternatives. TNT can be safely poured when liquid into shell cases, and is so insensitive that in 1910, it was exempted from the UK's Explosives Act 1875 and was not considered an explosive for the purposes of manufacture and storage.
The German armed forces adopted it as a filling for artillery shells in 1902. TNT-filled armour-piercing shells would explode after they had penetrated the armour of British capital ships, whereas the British lyddite-filled shells tended to explode upon striking armour, thus expending much of their energy outside the ship. The British started replacing lyddite with TNT in 1907. TNT is still widely used by the United States military and construction companies around the world. The majority of TNT currently used by the US military is manufactured by Radford Army Ammunition Plant near Radford, Virginia.
IUPAC NAME: 2-methyl-1,3,5-trinitrobenzene
OTHER NAME: 2,4,6-Trinitrotoluene, TNT, Trilite, Tolite, Trinol, Trotyl, Tritolo, Tritolol, Triton, Tritone, Trotol, Trinitrotoluol, 2,4,6-Trinitromethylbenzene
MOLECULAR FORMULA: C7H5N3O6
MOLAR MASS: 227,131 g/mol
SHOCK SENSITIVITY: Insensitive
FRICTION SENSITIVITY: Insensitive
EXPLOSIVE VELOCITY: 6,900 m/s
In a refined form, TNT is one of the most stable of high explosives and can be stored over long periods of time. It is relatively insensitive to blows or friction. It is nonhygroscopic and does not form sensitive compounds with metals, but it is readily acted upon by alkalies to form unstable compounds that are very sensitive to heat and impact. TNT may exude an oily brown liquid. This exudate oozes out around the threads at the nose of the shell and may form a pool on the floor. The exudate is flammable and may contain particles of TNT. Pools of exudate should be carefully removed.
TNT can be used as a booster or as a bursting charge for high-explosive shells and bombs.
It is a common misconception that TNT and dynamite are the same,
or that dynamite contains TNT. In fact, whereas TNT is a specific chemical compound, dynamite is an absorbent
mixture soaked in nitroglycerin that is compressed into a cylindrical shape and wrapped in paper.
TNT is a readily available and useful precursor to many other polynitroarylenes.
Many of the reactions utilizing TNT in this way make use of the acidity of the
methyl group protons. This is itself a consequence of the strengthened hyperconjugation in
TNT as a result of the large negative inductive effect generated by having three nitro groups
on the aromatic nucleus.
TNT is synthesized in a three-step process. First, toluene is nitrated with a mixture of sulfuric and nitric acid to produce mono-nitrotoluene or MNT. The MNT is then nitrated to dinitrotoluene or DNT. In the final step, the DNT is nitrated to trinitrotoluene or TNT. The acids used in the manufacture of TNT are recycled and reused.
Upon detonation, TNT decomposes as follows:
2 C7H5N3O6 --> 3 N2 + 5 H2O + 7 CO + 7 C
The reaction is exothermic but has a high activation energy. Because of the production of carbon, TNT explosions have a sooty appearance.
TNT is poisonous, and skin contact can cause skin irritation, causing the skin to turn a bright yellow-orange color.
During the First World War, munition workers who handled the chemical found that their skin turned bright yellow,
which resulted in their acquiring the nickname "canary girls" or simply "canaries."
People exposed to TNT over a prolonged
period tend to experience anemia and abnormal liver functions. Blood and liver effects, spleen enlargement and other harmful
effects on the immune system have also been found in animals that ingested or breathed trinitrotoluene. There is evidence that
TNT adversely affects male fertility, and TNT is listed as a possible human carcinogen. Consumption of TNT produces red urine
through the presence of breakdown products and not blood as sometimes believed.
Some military testing grounds are contaminated with TNT. Wastewater from munitions programs including contamination of
surface and subsurface waters may be colored pink because of the presence of TNT. Such contamination, called "pink water",
may be difficult and expensive to remedy.