Co-nitration of 1,2,4-butanetriol and glycerin

#This invention relates to nitrate esters and more particularly to methods of co-nitrating polyols to produce nitrate ester mixtures.

#Mixtures of 1,2,4-butanetriol trinitrate and nitroglycerin are useful as energetic components in explosives and gun propellants. Normally, 1,2,4-butanetriol and glycerin are nitrated separately to form 1,2,4-butanetriol trinitrate and nitroglycerin which are then blended together in the desired proportions. This requires that one of the nitrate esters be stored while the other is being made. This storage is undesirable because either nitroglycerin or 1,2,4-butanetriol trinitrate is more sensitive to impact than a blended mixture of the two. Moreover, fume-offs frequently occur during the nitration of 1,2,4-butanetriol alone. It would be desirable to provide a method of reducing or eliminating these problems.

#Accordingly, an object of this invention is to provide a new method of producing mixtures of 1,2,4-butanetriol trinitrate and nitroglycerin.

#To more clearly illustrate this invention, the following examples are presented. It should be understood, however, that these examples are presented merely as a means of illustration and are not intended to limit the scope of the invention in any way.

#46.6 grams of a binary solution of 53.1 weight percent of 1,2,4-butanetriol (96 percent pure) and 46.9 weight percent of glycerin at 41.degree. C. was pumped into 300 grams of mixed acid (38.1 weight percent of nitric acid and 58.8 weight percent of sulfuric acid) at 15.+-.1.degree. C. This is a 43 percent excess of nitric acid. During the nitration the mixture was agitated with a high-speed, high-shear mixer. During the nitration the change in redox was 80 mv. (A sample of this 1,2,4-butanetriol nitrated by itself had a change in redox of 130 mv.) The nitration mixture was drowned in 1000 grams of 6.degree. C. water with a 18.degree. C. temperature rise. The calculated spent acid analysis was:

#______________________________________ % Nitric Acid 11.8 % Sulfuric Acid 71.8 % Oxides 0.5 % Water assuming 1% NG 13.9 and 1% BTTN H.sub.2 O/H.sub.2 SO.sub.4 Mole Ratio 1.05 ______________________________________