Physico-chemical measurements of CL-20 for environmental applications. Comparison with RDX and HMX.
CL-20 is a polycyclic energetic nitramine, which may soon replace the monocyclic nitramines RDX and HMX, because of its superior explosive performance. Therefore, to predict its environmental fate, analytical and physico-chemical data must be made available. An HPLC technique was thus developed to measure CL-20 in soil samples based on the US Environmental Protection Agency method 8330. We found that the soil water content and aging (21 days) had no effect on the recoveries (>92%) of CL-20, provided that the extracts were kept acidic (pH 3). The aqueous solubility of CL-20 was poor (3.6 mg l(-1) at 25 degrees C) and increased with temperature to reach 18.5 mg l(-1) at 60 degrees C. The octanol-water partition coefficient of CL-20 (log KOW = 1.92) was higher than that of RDX (log KOW = 0.90) and HMX (log KOW = 0.16), indicating its higher affinity to organic matter. Finally, CL-20 was found to decompose in non-acidified water upon contact with glass containers to give NO2- (2 equiv.), N2O (2 equiv.), and HCOO- (2 equiv.). The experimental findings suggest that CL-20 should be less persistent in the environment than RDX and HMX.
Monteil-Rivera
Fanny
F
Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Que., H4P 2R2 Canada.
Paquet
Louise
L
Deschamps
Stéphane
S
Balakrishnan
Vimal K
VK
Beaulieu
Chantale
C
Hawari
Jalal
J
D001372:Aza Compounds / Q000032:analysis*; D001392:Azocines / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D006571:Heterocyclic Compounds / Q000032:analysis*; D006573:Heterocyclic Compounds, 1-Ring / Q000032:analysis*; D014227:Triazines / Q000032:analysis*
C482139:2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaaza-isowurtzitane; D001372:Aza Compounds; D001392:Azocines; D006571:Heterocyclic Compounds; D006573:Heterocyclic Compounds, 1-Ring; D014227:Triazines; C007950:octogen; C009160:cyclonite