Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) was separated out from polymer-bonded explosives (PBXs) by extraction with DMSO and crystallization with ethanol. The model PBX used herein was DXC-57, which is composed of HMX and Estane, a polyurethane-based binder. Crystallization at a higher degree of supersaturation (S, the ratio of concentration to solubility) lowered the possibility of the formation of the thermodynamically stable β-form HMX. Estane was found to retard the nucleation and to cause crystallization at high S. β-form HMX with purity greater than 99% was recovered from DXC-57 in over 90% yield via crystallization at S ≤ 6.26 followed by washing with THF.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)