Читать книгу Nitro-Explosives: A Practical Treatise - P. Gerald Sanford - Страница 23

but more recent researches rather point to its being regarded as a nitric ether of glycerol, or glycerine, and to its being formed thus—

C_{3}H_{8}O_{3} + 3 HNO_{3} = C{3}H_{5}(NO_{3}){3} + 3H{2}O. 92 227

|OH

The formula of glycerine is C_{3}H_{8}O_{8}, or C_{3}H_{5}|OH

|OH

|ONO_{2}

and that of the mono-nitrate of glycerine, C_{3}H_{5}|OH

|OH

|ONO_{2}

and of the tri-nitrate or (nitro-glycerine), C_{3}H_{5}|ONO_{2}

|ONO_{2}

that is, the three hydrogens of the semi-molecules of hydroxyl in the glycerine have been replaced by the NO_{2} group.

In the manufacture upon the large scale, a mixture of three parts by weight of nitric acid and five parts of sulphuric acid are used. From the above equation it will be seen that every 1 lb. of glycerol should give 2.47 lbs. of nitro-glycerol ((227+1)/92 = 2.47), but in practice the yield is only about 2 lbs. to 2.22, the loss being accounted for by the unavoidable formation of some of the lower nitrate, which dissolves in water, and is thus washed away, and partly perhaps to the presence of a little water (or other non-nitrable matter) in the glycerine, but chiefly to the former, which is due to the acids having become too weak.