The Analysis of Mono- and Divalent Cations Present in Explosive Residues Using Ion Chromatography with Conductivity Detection

Abstract

The separation of nine mono- and divalent cations of interest in explosives residue analysis was achieved using a Waters IC Pak-C Cation M/D column with a 3 mN HNO3 eluent and conductivity detection. The apparatus was then used to collect data on the types of cations found in a variety of explosive residues including black powder, smokeless powder, and ammonium nitrate based explosives.

Forensic identification of explosive oxidizers by electrospray ionization mass spectrometry

“…Since the introduction of ion chromatography in forensic laboratories in the early 1980s,6 it has become a routine procedure for the analysis of inorganic explosives. Ions such as K + , Na + , NH 4 + , Ca 2+ , NO 3 − , ClO 3 − , SO 4 2− and ClO 4 − have been successfully identified 7–9. However, in ion chromatography, the positive and negative ions in each oxidizer are analyzed separately on a cation and an anion column, which in some cases makes the identification of the oxidizer as one entity doubtful.…”

Characterization of ammonium nitrate by electrospray ionization tandem mass spectrometry

“…Ammonium nitrate, being a salt, is not amenable to gas‐phase mass spectrometry, and is usually analyzed by ion chromatography, which has become a routine procedure in forensic analysis of inorganic explosive compounds 2–4. Normally, ammonium and nitrate are independently analyzed on a cation and an anion column, respectively, which makes the true presence of integral AN in residues collected at bombing scenes questionable, as there is a possibility of presence of ammonium and nitrate ions in the background.…”

Characterisation of gunshot residue from three ammunition types using suppressed anion exchange chromatography

“…Though not investigated here, metal content in GSR often includes aluminium, arsenic, calcium, copper, mercury, sodium, potassium, strontium, zinc, lead, barium and antimony and can be present as the free metal or as ionic salts. The latter three metal species are normally used as dominant indicators of GSR using SEM-EDX [21]. Organic species bearing nitro, carboxylic acid and amine groups such as nitrotoluene, ascorbic acid, carbanilide, phenylamines and phthalate ester analogues should also be considered as a potential source of anionic species in GSR and could contribute increased levels of nitrite/nitrate, low molecular weight carboxylates (such as benzoate, phthalate or oxalate) and ammonium-based ions in addition to inorganic salt composition [22].…”