Abiotic formation of amorphous carbonaceous particles by aHMX (cyclotetramethylenetetranitramine) explosion experiment: implication from organic matter and the quench effect
Y. Takano1, K. Yamada2, T. Saiki3, M. Hayakawa3, H. Imamura3,M. Abe3, K. Tanaka4, M. Arakawa5, T. Nakamura6, H. Sugahara1,R. Okazaki7, T. Sawada3 and S. Tachibana81
Japan Agency for Marine-Earth Science & Technology(JAMSTEC), 2Tokyo Institute of Technology (TIT), 3Japan Aerospace Exploration Agency (JAXA), 4National Institute of Advanced Industrial Science & Technology (AIST), 5Kobe Univ.,
6Tohoku Univ., 7Kyushu Univ., 8Hokkaido Univ.
E-mail: takano@jamstec.go.jp.
HMX (putative High-Melting Explosive; i.e., cyclotetramethylenetetranitramine; chemical composition, C4H8N8O8; molecularweight, 296.15) is one of typical high explosives for producing
momentary driving force and is used for Small Carry-on Impactor (SCI), a scientific instrument for an artificial cratering experiment in the Hayabusa-2 mission [1]. To demonstrate the explosion product including from other compensate combustion
chemicals, we conducted a simulation experiment of HMX-based
explosion together with HTPB (Hydroxyl Terminated Polybutadiene), IDP (Isodecyl palargonate; C19H38O2) and IPDI (Isophorone diisocyanate; C12H18N2O2) under Ar atmosphere, ambient
temperature and pressure. After the explosion in the closed experimental box, we collected the gaseous sample, carbonaceous solid
products and relic of burst metal materials.
Firstly, morphological properties of solid carbonaceous particle products were observed by Scanning Electron Microscope
coupled with Energy Dispersive X-ray Spectroscope (SEMEDX). The analysis revealed rapid melting process of metal by
the HMX-based explosion and re-crystalized precipitation during
the quench effect. The size distribution of amorphous particles
were approximately 1-100 µm scale. We also confirmed carbonaceous / metal complex products containing initial metal components (e.g., Al, Cu, Fe, Cr). For further validation and feedback to
the operation [1], the carbon and nitrogen isotopic compositionsof the solid carbonaceous particles were determined by an isotope
ratio mass spectrometer.
Secondly, the volatile components were analyzed by a solidphase micro-extraction (SPME) coupled with gas chromatography/mass spectrometry (GC/MS). Wide variety of volatilecompounds including aliphatic and aromatic carbon structures
were detected. The functional groups of the products showed hydroxyl, aldehyde, nitrile, carboxyl and other labile groups. We
also confirmed the abiotic formation of involatile amino- and Nheterocyclic compounds extracted from the carbonaceous particles. Consequently, we suggest that the HMX-based explosion
nucleus was exposed to momentary high temperature (cf. melting
point of metal materials; Cu, 1084oC; SUS304, 1400-1450 oC),
whereas the quench effect would abiotically produce the various
labile organic matters without thermal degradation processes.
[1] Tachibana, S., Abe, M., Arakawa, M., Fujimoto, M., Iijima,Y., Ishiguro, M., Kitazato, K., Kobayashi, N., Namiki, N., Okada,T., Okazaki, R., Sawada, H., Sugita, S., Takano, Y., Tanaka, S.,
Watanabe, S., Yoshikawa, M., Kuninaka, H. and Hayabusa project team (2014) Hayabusa-2: Scientific importance of samples
returned from near-Earth C-type asteroid 1999 JU3. Geochemical
Journal, submitted.