Nitrogen oxide (N2O5) → Nitric Acid

Participants

Reaction Steps

U.S. Pat. No. 4,432,902, issued to McGuire, et al. on Feb. 21, 1984, teaches the formation of HMX by addition of dinitrogen pentoxide (N2O5) to a solution of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DADN): ##STR2## or 1,3,5,7-tetraazacyclooctane (TAT) in an unspecified solvent (which is understood to be anhydrous nitric acid) to form a solution of HMX. The solution is then poured into a bath of water (in which HMX is insoluble) to cause the HMX to crystallize. While the McGuire patent uses the reaction scheme preferred herein, beta HMX is not consistently produced because the reaction conditions, particularly at the point where the HMX solution is added to water, are not precisely controlled. McGuire discloses that a concentrated acid should be added to water suddenly (Example 14) to precipitate HMX. This causes localized or general exotherms which encourage formation of undesired polymorphs of HMX. McGuire's method has been shown to be difficult to practice on a larger than laboratory scale.

Provenance & Evidence