Dinitroglycerin

Dinitroglycerin wurde technisch durch Nitrieren von Glycerin mit Sal-petersaure hergestellt, wobei Gemische von Di- und Trinitroglycerin erhalten wurden. 

Any of these expls may be rendered low-freezing by incorporating NGc (Nirroglycol), DNG (Dinitroglycerin) or DNClH (Dinitro-chlorohydrin). Aromatic nitrocompounds, such as DNT and TNT, can be used for the same purpose... 

Dinitroglycerin Picrote or Glycerin-2,4,6-trinitrophenylether Dinitrate. See under Glycerin and Derivatives... 

A.Mikolajczak proposed in I9O3 and patentee the addn of dinitroglycerin (glycerin dinitrate), C,Hj (0HX0N02)2, and developed a simple method for its prepn... 

The same inventor patented (GerP 2007 of 1893) the following prepn of a-trinitrophenol-dinitroglycerine and dinitronaphthol-dinitro-glycerin One dissolves 20 p of dinitro-a-chlorhydrin in 60 p of alcohol, and the soln is mixed with 27 p of K picrate. After heating at 70—80° until the pptn of K chloride ceases, the soln is coned and then cooled to achieve crystn Ref Daniel (1902), 796... 

Further, nitroglycerine can be blended in all proportions with other liquid nitric esters, such as methyl nitrate, the so-called nitroglycol—ethylene glycol dinitrate, diethylene glycol dinitrate, dinitroglycerine, trimethylolnitromethane trinitrate (nitro-isobutylglycerine trinitrate), etc. 

In the system nitric acid-nitroglycerine-water, a labile equilibrium is established, determined by the coefficient of phase separation. Thus under certain conditions as much as 8% nitric acid passes into the water phase whereas the nitroglycerine does not contain more than 0.01% HNO3. A thorough study of the partition of HNO3 and dinitroglycerine between nitroglycerine and aqueous solutions was made by Oehman [108]. 

After separation of the nitroglycerine, the following remain in the spent acid nitroglycerine, dinitroglycerine, mixed esters of sulphuric and nitric arid. The two latter esters react slowly with the nitric arid contained in the waste arid to form further nitroglycerine, which floats on the surface of the arid. 

The addition of water to detain nitroglycerine in the spent acid not only increases the solubility of nitroglycerine in the acid, it also alters the equilibrium of the reaction between dinitroglycerine, nitroglycerine and acid in such a way that dinitroglycerine does not undergo further nitration and the trinitrate is not formed (Renner and Helle [28]). 

Pure a-mononitrate can be obtained by converting dinitroglycerine into nitroglycide" which in the presence of hot water is hydrolysed to form the mononitrate. Afterwards water is removed under reduced pressure ... 

GLYCEROL DINITRATE ( DINITROGLYCERINE ) Two isomeric glycerol dinitrates (dinitroglycerines) are known.. ... 

The isomers of dinitroglycerine have been separated by Will, Haanen and Stohrer [7], utilizing the capacity of the a-isomer to form a crystalline hydrate. Thus by cooling dinitroglycerine with a 3.2% water content, crystallization of the hydrate occurs, whilst the /3-isomer hydrate remains in solution. The a-isomer hydrate, melting at 26°C, has the formula [CjI OHXONO Jj.I O. It dissolves readily in water and benzene. At a temperature of 40°C both hydrates lose their combined water. 

As mentioned above, dinitroglycerine is hydrolysed in the cold in the presence of a concentrated potassium hydroxide solution to form nitroglycide. 

According to Naoum [8] the explosive decomposition of dinitroglycerine can be expressed by the equation ... 

The detonation rate of 92% dinitroglycerine blasting gelatine is 3300 m/sec, according to Blochmann [9] the corresponding value for nitroglycerine being 7000 m/sec. 

For a 75% Kieselguhr dynamite made from dinitroglycerine the rate of detonation is 4300 m/sec (with nitroglycerine it is 6800 m/sec). 

According to Blochmann transmission of detonation from a 100 g charge of blasting gelatine made from dinitroglycerine is 5 cm, whereas for nitroglycerine gelatine it is 25 cm. 

If nitrous and nitric oxides are present in the nitric acid, products of oxidation may contaminate the main product. Such dinitroglycerine should be washed with special care. The product is dried by passing a stream of warm air through it. 

The consumption of raw materials is such that the price of dinitroglycerine is higher than that of nitroglycerine. 

According to du Pont Company [10], ammonia can be used for the neutralization of the dilute solution of dinitroglycerine in nitric acid, thus producing a solution of ammonium nitrate which is recoverable. 

Piitz [11] obtained a patent for the preparation of dinitroglycerine relatively free from the trinitrate by dissolving 1 part of glycerine in 3.3 parts of nitric acid (sp. gr. 1.5) below 15°C. The solution was diluted with 1 part of water and neutralized with calcium carbonate. The product was separated as an oil and a small quantity was extracted with ether from the aqueous solution. 

Dinitroglycerine was also obtained from nitroglycerine by denitrating it with sulphuric acid [12, 25]. The denitration occurs simply by dissolving nitroglycerine in cone, sulphuric add without cooling. The solution is dissolved in water and the dinitroglycerine extracted with ether. 

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