Determination of inorganic anions in chemical ignition molotov cocktail using ion chromatography

Abstract

The Chemical Ignition Molotov Cocktail (CIMC) is one of the improvised incendiary devices (IIDs) that have been used recently in acts of terrorism. It is in the interest of the Police and Fire Department to gather information on the compositions and types of device employed by the determining the inorganic ions present in CIMCs residues, namely sulphate (SO4 2-), chlorate (ClO3 -), perchlorate (ClO4 -), and chloride (Cl-). In simulated ground experiments, these improvised CIMCs using petrol, kerosene and diesel as accelerants were thrown against a brick wall which initiated the fire as a consequence of the exothermic reaction produced by the combination of the concentrated sulfuric acid and potassium chlorate. Ion Chromatography (IC) was employed to determine the ionic composition of the CIMCs residues in order to identify the chemical reagents used for the device. The targeted anions were separated within 56 minutes using NaHCO3-Na2CO3 as the eluent. In this study, results from samples of CIMCs showed that sulfate, chlorate, and chloride were detected in most samples. However, perchlorate could not be detected since not all potassium chlorate reacted with sulfuric acid when the bottle broke. Concentration of sulfate ion was higher than the other anions. It was also noted that petrol gave the most powerful explosion on the CIMCs devices as compared to kerosene and diesel. Combustible material such as sugar was also found to give more destructive power on these devices as reflected by the more powerful combustion.