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2,4,6-TNT
¥ 80
2,3,6-TNT 2,3,4-TNT
m/z 227 m/z 227

Mass Range
225.5 - 226.5+
226.5 - 227.6

¥ 10
2,4-DNT
m/z 182

Mass Range
181.5 - 182.5

¥ 5
1,3,5-TNB
m/z 213

Mass Range
212.5 - 213.5

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Time (min)

Figure 6.9 LC/MS-APCI mass chromatograms of a TNT sample from the U.K.
(From Zhao, X. and Yinon, J., Characterization and origin identification of 2,4,6-
trinitrotoluene through its by-product isomers by liquid chromatography – atmo-
spheric pressure chemical ionization mass spectrometry, J. Chromatogr. A, 946,
125, 2002. With permission.)

process of TNT because of economic reasons. An additional reason is that
the isomer impurities affect the melting point and the crystallization prop-
29
erties and hence the casting properties of TNT. Pure 2,4,6-TNT has a
tendency to crystallize in a needlelike fashion which could cause voids and
cracks in shell and grenade fillings.
A series of additional nitroaromatic compounds (Scheme 4), 2,4,6-tri-
nitro-m-cresol (TNC), 2,4,6-trinitroaniline (picramide), and tetryl (2,4,6,N-
30
tetranitro-N-methylaniline) were analyzed by negative-ion ESI-MS, using
a Finnigan LCQ ion trap mass spectrometer. Samples were infused into the
mass spectrometer at a flow rate of 5 ml/min using a syringe pump. Samples

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