2,4-Dinitrotoluene (DNT) or dinitro is an
organic compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...
with the formula C
7H
6N
2O
4. This pale yellow
crystalline
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macrosc ...
solid is well known as a precursor to
trinitrotoluene
Troponin T (shortened TnT or TropT) is a part of the troponin complex, which are proteins integral to the contraction of skeletal and heart muscles. They are expressed in skeletal and cardiac myocytes. Troponin T binds to tropomyosin and help ...
(TNT) but is mainly produced as a precursor to
toluene diisocyanate.
Isomers of dinitrotoluene
Six
positional isomers are possible for dinitrotoluene. The most common one is 2,4-dinitrotoluene. The
nitration
In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group () into an organic compound. The term also is applied incorrectly to the different process of forming nitrate esters () between Alcohol ...
of
toluene
Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon with the chemical formula , often abbreviated as , where Ph stands for the phenyl group. It is a colorless, water
Water is an inorganic compound with the c ...
gives sequentially
mononitrotoluene, DNT, and finally TNT. 2,4-DNT is the principal product from dinitration, the other main product being about 30% 1,3-DN2-T. The nitration of
4-nitrotoluene gives 2,4-DNT.
Applications
Most DNT is used in the production of
toluene diisocyanate, which is used to produce flexible
polyurethane
Polyurethane (; often abbreviated PUR and PU) is a class of polymers composed of organic chemistry, organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane term ...
foams. DNT is
hydrogenated to produce
2,4-toluenediamine, which in turn is
phosgenated to give
toluene diisocyanate. In this way, about 1.4 billion kilograms are produced annually, as of the years 1999–2000.
Other uses include the explosives industry. It is not used by itself as an explosive, but some of the production is converted to TNT.
Dinitrotoluene is frequently used as a
plasticizer
A plasticizer ( UK: plasticiser) is a substance that is added to a material to make it softer and more flexible, to increase its plasticity, to decrease its viscosity, and/or to decrease friction during its handling in manufacture.
Plasticizer ...
, deterrent coating, and burn rate modifier in
propellant
A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or another motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicle ...
s (e.g.,
smokeless gunpowder
Finnish smokeless powder
Smokeless powder is a type of propellant used in firearms and artillery that produces less smoke and less fouling when fired compared to black powder. Because of their similar use, both the original black powder formula ...
s). As it is
carcinogen
A carcinogen () is any agent that promotes the development of cancer. Carcinogens can include synthetic chemicals, naturally occurring substances, physical agents such as ionizing and non-ionizing radiation, and biologic agents such as viruse ...
ic
[ and toxic, modern formulations tend to avoid its use. In this application it is often used together with ]dibutyl phthalate
Dibutyl phthalate (DBP) is an organic compound of phthalate which is commonly used as a plasticizer because of its low toxicity and wide liquid range. With the chemical formula C6H4(CO2C4H9)2, it is a colorless oil, although impurities often r ...
.
Toxicity
Dinitrotoluenes are highly toxic with a threshold limit value (TLV) of 1.5 mg/m3.NIOSH Pocket Guide to Chemical Hazards - Dinitroluene
/ref> It converts hemoglobin
Hemoglobin (haemoglobin, Hb or Hgb) is a protein containing iron that facilitates the transportation of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the sole exception of the fish family Channichthyidae. Hemoglobin ...
into methemoglobin
Methemoglobin (British: methaemoglobin, shortened MetHb) (pronounced "met-hemoglobin") is a hemoglobin ''in the form of metalloprotein'', in which the iron in the heme group is in the Fe3+ (ferric) state, not the Fe2+ (ferrous) of normal hemoglobin ...
.
2,4-Dinitrotoluene is also a listed hazardous waste under 40 CFR 261.24. Its United States Environmental Protection Agency
The Environmental Protection Agency (EPA) is an independent agency of the United States government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it began operation on De ...
(EPA) Hazardous Waste Number is D030. The maximum concentration that may be contained to not have toxic characteristics is 0.13 mg/L.
References
External links
*
{{DEFAULTSORT:Dinitrotoluene, 2,4-
Explosive chemicals
IARC Group 2B carcinogens
Nitrotoluenes
Plasticizers