The action of nitric acid on hexamine

CYCLONITE MANUFACTURE 1. THE ACTION OF NITRIC ACID ON HEXAMINE General information 

The oldest and simplest method of preparing cyclonite is based on the introduction of hexamethylenetetramine (hexamine) into an excess of concentrated nitric acid, s. g. 1.50-1.52, free of nitric oxides, at 25-30°C, thereafter pouring the whole into cold water. 

According to Hale [5] the reaction may be represented by the following equation x 

It appears however that the reaction proceeds according to both equations simultaneously since ammonium nitrate and formaldehyde are formed according to equation (37) and C02, N2 and water according to equation (38). Some of the methylene groups and nitrogen atoms of hexamine are therefore not utilized for the production of cyclonite. The nitration of hexamine with nitric acid requires from four to eight times the theoretical amount of nitric acid. 

Apart from the main reactions (37) and (38), side reactions (39) and (40) also take place. 

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The final product of the action of nitric acid on hexamine or hexamine dinitrate is RDX see Vol 3, p C614. At low temps, however a number of other compounds are produced (Ref 2). Dilution of the hexamine dinitrate-nitric acid reaction mixture at low temperatures with ethyl ether and subsequent treatment of the gum so obtained with methyl and ethyl alcohols and water severally leads to l-alkoxy-3 5-dinitro-l 3 5-triazacyclohexane (IV), l 3-di-nitro-l 3 5-triaza-n-pentane 5-nitrate (V), and methylenedi-1 -(3 5-dinitro-1 3 5-triaza-cyclo-hexane) (VI). Dilution of the reaction mixture with methyl and ethyl alcohol produces mainly 3 5-dinitro-1 3 5-triazacyclohexane nitrate (II). 

According to the investigations of Hirst, Carruthers et al. [41] and Vroom and Winkler [42], the action of nitric acid on hexamine dinitrate (IV) results in the formation of the substance (V) by nitrolysis. 

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