Solubility of Nitroglycerin in Spent Acid

Fig. 9. Solubility of nitroglycerine in spent acid, according to Klassen and Humphrys [25].

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]). 

In practice the nitrating conditions most frequently applied are those which permit the composition of the spent acids after nitration to approximate to the mixture My Naoiim [22] has established the solubility of nitroglycerine in mixed acids composed of ingredients resembling approximately the mixture M3 (Table 10),... 

The stronger the acid concentration, the higher the degree of nitration and the larger is the yield. An excess of acids establishes equilibria that favour a more complete reaction. The surplus must not be too large, however, since nitroglycerine is slightly soluble in spent acid and this may considerably decrease the yield of... 

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