Page 271 - Advances in Forensic Applications of Mass Spectrometry - Jehuda Yinon

1522_book.fm Page 244 Thursday, November 13, 2003 9:58 AM

mononitrotoluene (MNT), to dinitrotoluene (DNT), and to 2,4,6-trinitro-
toluene (TNT). Nitration is carried out in the presence of nitric and sulfuric
acid, followed by crystallization in alcohol or water, and washings with
sodium sulfite. The three steps of nitration can be carried out as batch
processes or as a continuous process.
Characterization of TNT was made possible by building an LC/MS-APCI
profile of byproducts, containing the isomers of TNT, DNT, DNB, and TNB. 26
MS/MS-CID was used as an additional dimension of identification for some
of the nitroaromatic isomers. Figure 6.7 to Figure 6.10 show the LC/MS-

2,4,6-TNT
¥ 50

2,3,4-TNT
m/z 227
Mass Range
225.5 - 226.5+
226.5 - 227.5

¥ 5
2,4-DNT
m/z 182

Mass Range
181.5 - 182.5

¥ 10

Mass Range
212.5 - 213.5

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

Figure 6.7 LC/MS-APCI mass chromatograms of a TNT sample from Russia.
(Reprinted from Zhao, X. and Yinon, J., Characterization and origin identification
of 2,4,6-trinitrotoluene through its by-product isomers by liquid chromatography
– atmospheric pressure chemical ionization mass spectrometry, J. Chromatogr.
A, 946, 125, 2002. Copyright 2002, with permission from Elsevier Science.)

© 2004 by CRC Press LLC