Nitroglycerin

Source: Wikipedia, the free encyclopedia.
Nitroglycerin
Skeletal formula of zwitterionic nitroglycerin
Ball and stick model of nitroglycerin
Spacefill model of nitroglycerin
Names
Preferred IUPAC name
Propane-1,2,3-triyl trinitrate
Other names
  • 1,2,3-Tris(nitrooxy)propane
  • 1,2,3-Trinitroxypropane
  • Glyceryl trinitrate
  • GTN
  • Nitro
  • TNG
  • Trinitroglycerin
  • alpha,alpha,alpha-Trinitroglycerin
Identifiers
3D model (
JSmol
)
1802063
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard
100.000.219 Edit this at Wikidata
EC Number
  • 200-240-8
165859
IUPHAR/BPS
KEGG
MeSH Nitroglycerin
UNII
UN number 0143, 0144, 1204, 3064, 3319
  • InChI=1S/C3H5N3O9/c7-4(8)13-1-3(15-6(11)12)2-14-5(9)10/h3H,1-2H2 checkY
    Key: SNIOPGDIGTZGOP-UHFFFAOYSA-N checkY
  • InChI=1/C3H5N3O9/c7-4(8)13-1-3(15-6(11)12)2-14-5(9)10/h3H,1-2H2
    Key: SNIOPGDIGTZGOP-UHFFFAOYAR
  • C(C(CO[N+](=O)[O-])O[N+](=O)[O-])O[N+](=O)[O-]
Properties
C3H5N3O9
Molar mass 227.085 g·mol−1
Appearance Colorless liquid
Density 1.6 g⋅cm−3 (at 15 °C)
Melting point 14 °C (57 °F; 287 K)
Boiling point 50 °C (122 °F; 323 K) Explodes
Slightly[1]
Solubility Acetone, ether, benzene, alcohol[1]
log P 2.154
Structure
  • Tetragonal at C1, C2, and C3
  • Trigonal planar at N7, N8, and N9
  • Tetrahedral at C1, C2, and C3
  • Dihedral at N7, N8, and N9
Explosive data
Shock sensitivity High
Friction sensitivity High
Detonation velocity 7,700 m/s
RE factor
1.50
Thermochemistry
Std enthalpy of
formation
fH298)
−370 kJ⋅mol−1
Std enthalpy of
combustion
cH298)
−1.529 MJ⋅mol−1
Pharmacology
C01DA02 (WHO) C05AE01 (WHO)
Intravenous, by mouth, under the tongue, topical
Pharmacokinetics:
<1%
Liver
3 min
Legal status
  • AU: S3 (Pharmacist only)
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Explosive, toxic
GHS labelling:
GHS02: Flammable GHS06: Toxic GHS08: Health hazard GHS01: Explosive
Danger
H202, H205, H241, H301, H311, H331, H370
P210, P243, P250, P260, P264, P270, P271, P280, P302+P352, P410
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability 4: Readily capable of detonation or explosive decomposition at normal temperatures and pressures. E.g. nitroglycerinSpecial hazards (white): no code
3
2
4
NIOSH (US health exposure limits):
PEL (Permissible)
C 0.2 ppm (2 mg/m3) [skin][2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Nitroglycerin (NG) (alternative spelling of nitroglycerine), also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily,

organic nitrate compound rather than a nitro compound, but the traditional name is retained. Discovered in 1847 by Ascanio Sobrero, nitroglycerin has been used as an active ingredient in the manufacture of explosives, namely dynamite, and as such it is employed in the construction, demolition, and mining industries. It is combined with nitrocellulose to form double-based smokeless powder, which has been used as a propellant
in artillery and firearms since the 1880s.

Nitroglycerin has been used for over 130 years

sublingual tablets, sprays, ointments, and patches.[5]

History

Nitroglycerin was the first practical explosive produced that was stronger than

black powder. It was synthesized by the Italian chemist Ascanio Sobrero in 1847, working under Théophile-Jules Pelouze at the University of Turin.[6] Sobrero initially called his discovery pyroglycerine and warned vigorously against its use as an explosive.[7]

Nitroglycerin was adopted as a commercially useful explosive by Alfred Nobel, who experimented with safer ways to handle the dangerous compound after his younger brother, Emil Oskar Nobel, and several factory workers were killed in an explosion at the Nobels' armaments factory in 1864 in Heleneborg, Sweden.[8]

One year later, Nobel founded

Alfred Nobel and Company in Germany and built an isolated factory in the Krümmel hills of Geesthacht near Hamburg. This business exported a liquid combination of nitroglycerin and gunpowder called "Blasting Oil", but this was extremely unstable and difficult to handle, as evidenced in numerous catastrophes.[9] The buildings of the Krümmel factory were destroyed twice.[10]

In April 1866, several crates of nitroglycerin were shipped to

Sierra Nevada Mountains. One of the remaining crates exploded, destroying a Wells Fargo company office in San Francisco and killing 15 people. This led to a complete ban on the transportation of liquid nitroglycerin in California. The on-site manufacture of nitroglycerin was thus required for the remaining hard-rock drilling and blasting required for the completion of the First transcontinental railroad in North America.[11]

On Christmas Day 1867, an attempt to dispose of nine canisters of Blasting Oil that had been illegally stored at the White Swan Inn in the centre of Newcastle upon Tyne resulted in an explosion on the Town Moor that killed eight people. In June 1869, two one-ton wagons loaded with nitroglycerin, then known locally as Powder-Oil, exploded in the road at the North Wales village of Cwm-y-glo. The explosion led to the loss of six lives, many injuries and much damage to the village. Little trace was found of the two horses. The UK Government was so alarmed at the damage caused and what could have happened in a city location (these two tons were part of a larger load coming from Germany via Liverpool) that they soon passed the Nitro-Glycerine Act of 1869.[12] Liquid nitroglycerin was widely banned elsewhere, as well, and these legal restrictions led to Alfred Nobel and his company's developing dynamite in 1867. This was made by mixing nitroglycerin with diatomaceous earth ("Kieselguhr" in German) found in the Krümmel hills. Similar mixtures, such as "dualine" (1867), "lithofracteur" (1869), and "gelignite" (1875), were formed by mixing nitroglycerin with other inert absorbents, and many combinations were tried by other companies in attempts to get around Nobel's tightly held patents for dynamite.

Dynamite mixtures containing nitrocellulose, which increases the viscosity of the mix, are commonly known as "gelatins".

Following the discovery that amyl nitrite helped alleviate chest pain, the physician William Murrell experimented with the use of nitroglycerin to alleviate angina pectoris and to reduce the blood pressure. He began treating his patients with small diluted doses of nitroglycerin in 1878, and this treatment was soon adopted into widespread use after Murrell published his results in the journal The Lancet in 1879.[13][14] A few months before his death in 1896, Alfred Nobel was prescribed nitroglycerin for this heart condition, writing to a friend: "Isn't it the irony of fate that I have been prescribed nitro-glycerin, to be taken internally! They call it Trinitrin, so as not to scare the chemist and the public."[15] The medical establishment also used the name "glyceryl trinitrate" for the same reason.

Wartime production rates

Large quantities of nitroglycerin were manufactured during

Royal Navy Cordite Factory, Holton Heath, in Dorset, England. A large cordite factory was also built in Canada during World War I. The Canadian Explosives Limited cordite factory at Nobel, Ontario
, was designed to produce 1,500,000 lb (680 t) of cordite per month, requiring about 286 tonnes of nitroglycerin per month.

Instability and desensitization

In its undiluted form, nitroglycerin is a

PETN
.

Early in its history, liquid nitroglycerin was found to be "

desensitized" by freezing it at a temperature below 45 to 55 °F (7 to 13 °C) depending on its purity.[16] Its sensitivity to shock while frozen is somewhat unpredictable: "It is more insensitive to the shock from a fulminate cap or a rifle ball when in that condition but on the other hand it appears to be more liable to explode on breaking, crushing, tamping, etc."[17] Frozen nitroglycerine is much less energetic than liquid, and so must be thawed before use.[18] Thawing it out can be extremely sensitizing, especially if impurities are present or the warming is too rapid.[19] Ethylene glycol dinitrate or another polynitrate may be added to lower the melting point and thereby avoid the necessity of thawing frozen explosive.[20]

Chemically "desensitizing" nitroglycerin is possible to a point where it can be considered about as "safe" as modern

high explosives, such as by the addition of ethanol, acetone, or dinitrotoluene.[21] The nitroglycerin may have to be extracted from the desensitizer chemical to restore its effectiveness before use, for example by adding water to draw off ethanol used as a desensitizer.[21]

Detonation

When nitroglycerin explodes the products after cooling are given by:

C3H5N3O9 → 3CO2 + 2.5H2O + 1.5N2 + 0.25O2

The heat released can be calculated from the heats of formation. Using −371 kJ/mol for the heat of formation of condensed phase nitroglycerin[22] gives 1414 kJ/mol released if forming water vapor, and 1524 if forming liquid water.

The detonation velocity of nitroglycerin is 7820 meters per second, which is about 113% the speed of TNT. Accordingly, nitroglycerin is considered to be a high-brisance explosive, which is to say, it has excellent shattering ability. The heat liberated during detonation raises the temperature of the gaseous byproducts to about 5,000 °C (9,000 °F).[20] With a standard enthalpy of explosive decomposition of −1414 kJ/mol and a molecular weight of 227.0865 g/mol, nitroglycerin has a specific explosive energy density of 1.488 kilocalories per gram, or 6.23 kJ/g, making nitroglycerin 49% more energetic on a mass basis than the standard definitional value assigned to TNT (precisely 1 kcal/g).

Manufacturing

Nitroglycerin can be produced by acid-catalyzed nitration of glycerol (glycerin).

Nitroglycerin synthesis:[23][24][25]

The industrial manufacturing process often reacts

azeotropic nitric acid (consisting of about 70% nitric acid, with the rest being water).[26]

The

protonated nitric acid species, which are attacked by glycerol's nucleophilic oxygen atoms. The nitro group is thus added as an ester C−O−NO2 and water is produced. This is different from an electrophilic aromatic substitution reaction in which nitronium ions are the electrophile
.

The addition of

glycerin addition at about 22 °C (72 °F), hot enough for esterification to occur at a fast rate but cold enough to avoid runaway reaction. The nitrator vessel, often constructed of iron or lead and generally stirred with compressed air
, has an emergency trap door at its base, which hangs over a large pool of very cold water and into which the whole reaction mixture (called the charge) can be dumped to prevent an explosion, a process referred to as drowning. If the temperature of the charge exceeds about 30 °C (86 °F) (actual value varying by country) or brown fumes are seen in the nitrator's vent, then it is immediately drowned.

Use as an explosive and a propellant

The main use of nitroglycerin, by tonnage, is in explosives such as dynamite and in propellants.

Nitroglycerin is an oily liquid that may explode when subjected to heat, shock, or flame.

military engineers
have used dynamite for construction and demolition work.

Nitroglycerin was also used as an ingredient in military propellants for use in

firearms
.

Nitroglycerin has been used in conjunction with

TNT.[28]

Nitroglycerin has an advantage over some other high explosives that on detonation it produces practically no visible smoke. Therefore, it is useful as an ingredient in the formulation of various kinds of smokeless powder.[29]

Its sensitivity has limited the usefulness of nitroglycerin as a military explosive, and less sensitive explosives such as

TNT, RDX, and HMX have largely replaced it in munitions. It remains important in military engineering, and combat engineers
still use dynamite.

Alfred Nobel then developed

guncotton. He patented it in 1887. Ballistite was adopted by a number of European governments, as a military propellant. Italy was the first to adopt it. The British government and the Commonwealth governments adopted cordite instead, which had been developed by Sir Frederick Abel and Sir James Dewar of the United Kingdom in 1889. The original Cordite Mk I consisted of 58% nitroglycerin, 37% guncotton, and 5.0% petroleum jelly
. Ballistite and cordite were both manufactured in the form of "cords".

Smokeless powders were originally developed using nitrocellulose as the sole explosive ingredient. Therefore, they were known as single-base propellants. A range of smokeless powders that contains both nitrocellulose and nitroglycerin, known as double-base propellants, were also developed. Smokeless powders were originally supplied only for military use, but they were also soon developed for civilian use and were quickly adopted for sports. Some are known as sporting powders. Triple-base propellants contain nitrocellulose, nitroglycerin, and

. This was an early, low-cost, flexible explosive.

Medical use

Nitroglycerin belongs to a group of drugs called nitrates, which includes many other nitrates like isosorbide dinitrate (Isordil) and isosorbide mononitrate (Imdur, Ismo, Monoket).[30] These agents all exert their effect by being converted to nitric oxide in the body by mitochondrial aldehyde dehydrogenase (ALDH2),[4] and nitric oxide is a potent natural vasodilator.

Nitro - bangy stuff
Nitroglycerin in three different forms: intravenous, sublingual spray, and the nitroglycerin patch.

In

ischemic heart disease caused by inadequate flow of blood and oxygen to the heart and as a potent antihypertensive agent. Nitroglycerin corrects the imbalance between the flow of oxygen and blood to the heart and the heart's energy demand.[30] There are many formulations on the market at different doses. At low doses, nitroglycerin dilates veins more than arteries, thereby reducing preload (volume of blood in the heart after filling); this is thought to be its primary mechanism of action. By decreasing preload, the heart has less blood to pump, which decreases oxygen requirement since the heart does not have to work as hard. Additionally, having a smaller preload reduces the ventricular transmural pressure (pressure exerted on the walls of the heart), which decreases the compression of heart arteries to allow more blood to flow through the heart. At higher doses, it also dilates arteries, thereby reducing afterload (decreasing the pressure against which the heart must pump).[30] An improved ratio of myocardial oxygen demand to supply leads to the following therapeutic effects during episodes of angina pectoris: subsiding of chest pain, decrease of blood pressure, increase of heart rate, and orthostatic hypotension. Patients experiencing angina when doing certain physical activities can often prevent symptoms by taking nitroglycerin 5 to 10 minutes before the activity. Overdoses may generate methemoglobinemia.[31][32]

Nitroglycerin is available in tablets, ointment, solution for

sublingually. Some forms of nitroglycerin last much longer in the body than others. Nitroglycerin as well as the onset and duration of action of each form is different. The sublingual or tablet spray of nitroglycerin has a two minute onset and twenty five minute duration of action. The oral formulation of nitroglycerin has a thirty five minute onset and a duration of action of 4–8 hours. The transdermal patch has an onset of thirty minutes and a duration of action of ten to twelve hours. Continuous exposure to nitrates has been shown to cause the body to stop responding normally to this medicine. Experts recommend that the patches be removed at night, allowing the body a few hours to restore its responsiveness to nitrates. Shorter-acting preparations of nitroglycerin can be used several times a day with less risk of developing tolerance.[33] Nitroglycerin was first used by William Murrell to treat angina attacks in 1878, with the discovery published that same year.[14][34]

Industrial exposure

Infrequent exposure to high doses of nitroglycerin can cause severe headaches known as "NG head" or "bang head". These headaches can be severe enough to incapacitate some people; however, humans develop a tolerance to and dependence on nitroglycerin after long-term exposure. Although rare, withdrawal can be fatal.[35] Withdrawal symptoms include chest pain and other heart problems. These symptoms may be relieved with re-exposure to nitroglycerin or other suitable organic nitrates.[36]

For workers in nitroglycerin (NTG) manufacturing facilities, the effects of withdrawal sometimes include "Sunday heart attacks" in those experiencing regular nitroglycerin exposure in the workplace, leading to the development of tolerance for the venodilating effects. Over the weekend, the workers lose the tolerance, and when they are re-exposed on Monday, the drastic vasodilation produces a fast heart rate, dizziness, and a headache. This is referred to as "Monday disease."[37][38]

People can be exposed to nitroglycerin in the workplace by breathing it in, skin absorption, swallowing it, or eye contact. The

immediately dangerous to life and health.[39]

See also

References

  1. ^ a b "Occupational Safety and Health Guideline for Nitroglycerin". Archived from the original on 16 May 2013. Retrieved 19 October 2016.
  2. ^ NIOSH Pocket Guide to Chemical Hazards. "#0456". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ "Hazard Rating Information for NFPA Fire Diamonds". Archived from the original on 17 February 2015.
  4. ^
    PMID 16103363
    .
  5. ^ "Unknown, behind paywall, archived". Archived from the original on 10 May 2017. Retrieved 14 April 2018.
  6. ^ Sobrero, Ascagne (1847). "Sur plusieur composés détonants produits avec l'acide nitrique et le sucre, la dextrine, la lactine, la mannite et la glycérine" [On several detonating compounds produced with nitric acid and sugar, dextrin, lactose, mannitol, and glycerin]. Comptes Rendus. 24: 247–248.
  7. ^ Sobrero, Ascanio (1849). "Sopra alcuni nuovi composti fulminanti ottenuti col mezzo dell'azione dell'acido nitrico sulle sostante organiche vegetali" [On some new explosive products obtained by the action of nitric acid on some vegetable organic substances]. Memorie della Reale Accademia delle Scienze di Torino. 2nd Series. 10: 195–201. On p. 197, Sobrero names nitroglycerin "pyroglycerine":
    "Quelle gocciole costituiscono il corpo nuovo di cui descriverò ora le proprietà, e che chiamerò Piroglicerina." (Those drops constitute the new substance whose properties I will now describe, and which I will call "pyroglycerine".)
  8. ^ "Emil Nobel". NobelPrize.org. Archived from the original on 15 January 2009. Retrieved 6 October 2008.
  9. ^ Ramsay, Sir William. "The Manufacture of High Explosives". Scientific American. Springer Nature. Retrieved 4 March 2024.
  10. ^ "Krümmel". NobelPrize.org. Archived from the original on 10 July 2006..
  11. PBS
    .
  12. ^ North Wales Daily Post newspaper of October 14th 2018.
  13. PMC 5901592
    .
  14. ^ .
  15. ^ "History of TNG". beyonddiscovery.org. Archived from the original on 1 November 2010. Retrieved 14 April 2018.
  16. ^ "Is Nitroglycerine In This? Page 5". www.logwell.com. Retrieved 20 February 2024.
  17. ^ Hurter, Charles S. (22 August 1911). "Accidents in the Transportation, Storage, and Use of Explosives" (PDF). Proceedings of the Lake Superior Mining Institute. 16: 70.
  18. ^ Hurter, Charles S. (22 August 1911). "Accidents in the Transportation, Storage, and Use of Explosives" (PDF). Proceedings of the Lake Superior Mining Institute. 16: 71.
  19. ^ Tallini, Rick F. "Tales of Destruction...Thawing Can Be Hell". Analog. Analog Services, Inc.
  20. ^ a b "Nitroglycerin". Encyclopaedia Britannica. Archived from the original on 12 September 2002. Retrieved 23 March 2005.
  21. ^ a b Tallini, Rick F. "Tales of Destruction...Is Nitroglycerin In This?". Analog Services, Inc.
  22. ^ Informatics, NIST Office of Data and. "Nitroglycerin". webbook.nist.gov. Retrieved 20 February 2024.
  23. .
  24. .
  25. .
  26. .
  27. ^ Bellis, Mary. "Alfred Nobel and the History of Dynamite". About.com Money. Archived from the original on 28 August 2021. Retrieved 10 November 2009.
  28. Bibcode:1976sots.rept...98M. Archived from the original
    (PDF) on 2 October 2018. Retrieved 27 March 2015.
  29. ^ "Nitroglycerin".
  30. ^ a b c Ogbru, Omudhome. "nitroglycerin, Nitro-Bid: Drug Facts, Side Effects and Dosing". MedicineNet.
  31. PMID 3917597
    .
  32. ^ "IntraMed – Bienvenido". www.intramed.net. Retrieved 14 April 2018.
  33. ^ "Nitroglycerin for angina, February 1997, Vol. 7". Archived from the original on 10 May 2017. Retrieved 9 November 2009.
  34. PMID 4998847
    .
  35. .
  36. . Retrieved 23 April 2013.
  37. .
  38. ^ Assembly of Life Sciences (U.S.) Advisory Center on Toxicology. Toxicological Reports. National Academies. p. 115. NAP:11288. Retrieved 23 April 2013.
  39. ^ "Nitroglycerine". NIOSH Pocket Guide to Chemical Hazards. CDC. Retrieved 21 November 2015.

External links