Ethylene glycol dinitrate
Encyclopedia
Ethylene glycol dinitrate (EGDN,NGc), also known as nitroglycol, is a chemical compound
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 a yellowish, oily explosive liquid obtained by nitrating
Nitration
Nitration is a general chemical process for the introduction of a nitro group into a chemical compound. The dominant application of nitration is for the production of nitrobenzene, the precursor to methylene diphenyl diisocyanate...

 ethylene glycol
Ethylene glycol
Ethylene glycol is an organic compound widely used as an automotive antifreeze and a precursor to polymers. In its pure form, it is an odorless, colorless, syrupy, sweet-tasting liquid...

. It is similar to nitroglycerin in both manufacture and properties, though it is more volatile and less viscous
Viscosity
Viscosity is a measure of the resistance of a fluid which is being deformed by either shear or tensile stress. In everyday terms , viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, while honey is "thick", having a higher viscosity...

.

History and production

L. Henry was the first who prepared EGDN in a pure state (1870) by dropping small portions of glycole into mixture of nitric
Nitric acid
Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...

 and sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...

s cooled to 0 deg. A. Kekulé previously (1869) nitrated ethylene
Ethylene
Ethylene is a gaseous organic compound with the formula . It is the simplest alkene . Because it contains a carbon-carbon double bond, ethylene is classified as an unsaturated hydrocarbon. Ethylene is widely used in industry and is also a plant hormone...

 and obtaned an unstable material, which was presumed to be Glycole Nitrite-Nitrate, but which in 1920 was shown by Wieland & Sakellarios to be a mixture of EGDN and nitric ester \beta-Nitroethyl Alcohol.
Other investigators preparing NGc before publication in 1926 of Rinkenbach's work included:
Champion (1871), Neff (1899) & Wieland & Sakellarios (1920), Dautriche, Hough & Oehme.
Rinkenbach prepared EGDN by nitrating purified glycol obtained by fractioning the commercial product under pressure of 40mm Hg, and at temp 120 deg. For this 20g of middle fraction of purified glycol was gradually added to mixture of 70g nitric acid and 130g sulfuric acid, maintaining the temp at 23 deg.The resulting 49g of crude product was washed with 300ml of water to obtain 39.6g of purified product. The low yield so obtained could be improved by maintaining a lower temperature and using a different nitrating acid mixture.

The book of Naoum are describing several methods of laboratory and industrial preparation of EGDN, such as:
1) Direct Nitration of Glycol is carried out in exactly the same manner, with the same apparatus, and with the same mixed acids as nitration of glycerine.
In the test nitration of anhydrous glycol (100g) with 625g of mixed acid 40 & 60% at 10-12 deg, the yield was 222g and it dropped to 218g when the temp was raised to 29-30 deg.
When 500g of mixed acid 50 & 50% was used at 10-12 deg, the yield increased to 229g.
In commercial nitration, the yields obtained from 100 kg anhydrous glycol and 625 kg of mixed acid containing 41, 58 & water 1% were 222.2 kg of NGc at nitrating temp of 10-12 deg and only 218.3 kg at 29-30 deg.
This means 90.6% of theory, as compared to 93.6% with NG.
2) Direct Production of NGc from Gaseous Ethylene.
This method was introduced after World War I by the Chemische Fabrik Kalk, GmbH in Köln-Kalk by Dr H. Oehme and later patented in USA.
3) Preparation of NGc from Ethylene Oxide.
4) Preparation of NGc by method of Messing from ethylene through
chlorohydrin & ethylene oxide.
5) Preparation of NGc by duPont method.

Properties

Molar weight 152.07, N 18.42%, OB to CO2 0%, OB to CO +21%; colorless volatile liquid when in pure state; yellowish liquid in crude state; sp gr 1.488 at 20/4° or 1.480 at 25°;
n_D 1.4452 at 25° or 1.4472 at 20°; freezing point -22.75° (vs +13.1° for NG); frozen point given in is -22.3°; boiling point 199° at 760mm Hg (with decomposition).

Wieland & Sakellarios ( quote at p1499) found EGDN to boil at 105.5° under a pressure of 19mm Hg, but when quickly heated under atmosphere pressure it exploded at 215°.
This was preceded by partial decomposition analogous to that found in case of NG.

Brisance by lead block compression (Hess crusher test) --- 30.0mm, vs 18.5mm for NG and 16mm for TNT. Brisance by sand test, determined in mixtures with 40% kieselguhr, gave for NGc mixtures slightly higher results then with those containing NG.
Chemical properties. On heating with solutions of alkalies, gradual solution with saponification, similar to NG, takes place.
With KOH, NGc reacts violently with formation of K nitrate and glycolate.
Chemical test for purity is conducted with Nitrometer Method, originated by Lange but modified by duPont Co.
N content of NGc should be about 18.42%, vs 18.50 for NG.
Critical temperature -- 114-116 degrees.

Other

EGDN was used in manufacturing explosives to lower the freezing point of nitroglycerin, in order to produce dynamite
Dynamite
Dynamite is an explosive material based on nitroglycerin, initially using diatomaceous earth , or another absorbent substance such as powdered shells, clay, sawdust, or wood pulp. Dynamites using organic materials such as sawdust are less stable and such use has been generally discontinued...

 for use in colder weather. Due to its volatility it did serve as a detection taggant
Taggant
A taggant can mean a radio frequency microchip used in automated identification and data capture . In such cases, electronic devices use radio waves to track and identify items, such as pharmaceutical products, by assigning individual serial numbers to the containers holding each product...

 in some plastic explosive
Plastic explosive
Plastic explosive is a specialised form of explosive material. It is a soft and hand moldable solid material. Plastic explosives are properly known as putty explosives within the field of explosives engineering....

s, e.g. Semtex
Semtex
Semtex is a general-purpose plastic explosive containing RDX and PETN. It is used in commercial blasting, demolition, and in certain military applications. Semtex became notoriously popular with terrorists because it was, until recently, extremely difficult to detect, as in the case of Pan Am...

, to allow more reliable explosive detection
Explosive detection
Explosive detection is a non-destructive inspection process to determine whether a container contains explosive material. Explosive detection is commonly used at airports, ports and for border control.-Dogs:...

, until 1995 when it was replaced by Dimethyldinitrobutane
DMDNB
DMDNB, or also DMNB, chemically 2,3-dimethyl-2,3-dinitrobutane, is a volatile organic compound used as a detection taggant for explosives, mostly in the United States where it is virtually the only such taggant in use. Dogs are very sensitive to it and can detect as little as 0.5 parts per billion...

. It is considerably more stable than glyceryl trinitrate
Glyceryl trinitrate
Glyceryl trinitrate is a chemical substance used as:* a drug; see glyceryl trinitrate * an explosive; see nitroglycerin...

 owing to the lack of secondary hydroxyl groups in the precursor polyol
Polyol
A polyol is an alcohol containing multiple hydroxyl groups. In two technological disciplines the term "polyol" has a special meaning: food science and polymer chemistry.- Polyols in food science :...

.

Like other organic nitrates, ethylene glycol dinitrate is a vasodilator.

See also

  • Methyl nitrate
    Methyl nitrate
    Methyl nitrate is the methyl ester of nitric acid and has the chemical formula CH3NO3.Methyl nitrate is toxic and a sensitive explosive. It causes headaches when fumes are inhaled...

  • Nitroglycerine
  • Erythritol tetranitrate
    Erythritol tetranitrate
    Erythritol tetranitrate is an explosive compound chemically similar to PETN. It is however thought to be 1/3 more sensitive to friction and impact. ETN is not well known, but in recent years has been used by amateur experimenters to replace PETN in improvised detonation cord or in boosters to...

  • Xylitol pentanitrate
    Xylitol pentanitrate
    Xylitol pentanitrate is a rarely used liquid explosive compound with extremely high viscosity formed by completely nitrating xylitol, a sugar alcohol compound with five carbon atoms. In pure form it is a white crystalline explosive, much like other fully nitrated polyols...

  • Mannitol hexanitrate

External links

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