Identification of Residues of Improvised Explosives Using Physico-Chemical Analytical Methods under Real Conditions

Abstract

When analyzing the cases of the criminal use of explosives, a shift has been found from industrial explosives towards substances prepared in unprofessional and illegal way. Therefore, a project is being implemented, based on an assessment of particular information available in the literature and on the internet. It aims at choosing specific groups of potentially abusable substances (e.g. mixtures of organic substances with nitric acid (98 %), nitromethane and tetranitromethane or chlorates and perchlorates of alkali metals, or, alternatively, single-component substances, such as heavy metal salts of perchloric acid, azides, fulminates, acetylides, picrates, styphnates, etc.). The current project deals with the preparation of these explosives (also in non-stoichiometric mixtures). In the next step, explosives have been tested, their explosive characteristics determined (if they are not known) and the analyses of both primary phases and post-blast residues performed. For this purpose, available analytical techniques have been used, such as gas and liquid chromatography/mass spectrometry, FTIR, micro-Raman spectrometry, electron microscopy with microanalysis and Raman microspectrometry directly in the SEM chamber for the analysis at the level of individual microparticles. The characteristics received will be used to extend the knowledge database for security forces.