Nitroglycerines Dinitroglycerines

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. 

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]. 

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]). 

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. 

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

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. 

Dinitroglycerin does not differ greatly from nitroglycerin in its explosive properties. It is appreciably soluble in water, and more expensive and more difficult to manufacture than nitrogly-... 

The dinitroglycerin obtained by the nitration of glycerin is a colorless, odorless oil, more viscous and more volatile than nitroglycerin. It causes the same kind of a headache. It has a specific gravity of 1.51 at 15°, boils at 146-148° at 15 mm. with only slight decomposition, and solidifies at —40° to a glassy solid which melts if the temperature is raised to —30°. It is readily... 

Dinitroglycerin gelatinizes collodion nitrocotton rapidly at ordinary temperature. The gel is sticky, less elastic, and more easily deformed than a nitroglycerin gel. Unlike the latter it is hygroscopic, and becomes softer and greasier from the absorption of moisture from the air. Water dissolves out the dinitroglycerin and leaves the nitrocellulose as a tough, stiff mass. 

Mononitroglycerin is a by-product in the preparation of dinitroglycerin and is separated from the latter substance by its greater solubility in water. It is usually obtained as a colorless oil, density 1.417 at 15°, more viscous than dinitroglycerin and less viscous than nitroglycerin. This oil is a mixture of the two isomers which are crystalline when separate but show little tendency to crystallize when they are mixed. a-Mononitroglycerin when pure consists of colorless prisms, m.p. 58-59°, specific gravity 1.53 at 15° it yields both of the dinitrates on nitration. The -compound crystallizes in dendrites and leaflets, m.p. 54°, and is more readily soluble in ether than the a-compound it yields only the a,/ -dinitrate on nitration. Both isomers boil at 155-160° at 15 mm. 

Once absorbed, the unchanged nitrate compounds have half-lives of only 2-8 minutes. The partially denitrated metabolites have much longer half-lives (up to 3 hours). Of the nitroglycerin metabolites (two dinitroglycerins and two mononitro forms), the dinitro derivatives have significant vasodilator... 

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