Investigation on improvised explosive devices and the physieochemical nature of the fuel binders

摘要

Exhibits of a series of bomb blasts (IED or Improvised Explosive Devices) in Southern parts of West Bengal, sent to the CFSL (Central Forensic Science Laboratory) showed that the explosives contained ammonium nitrate, sodium/potassium nitrate, traces of chlorides, sulfate etc. and paint grade aluminum powder with fuels sparingly soluble in acetone but soluble in ether. Gas chromatography-Mass spectrometry analysis of fuel oils (1-6) and fuels in the explosives indicated the absence of fuel oils. GC-MS analysis of ethereal solutions of wax collected from candle sticks available in the market showed the fuels used in the explosives were easily available ordinary wax though a number of explosives contained synthetic wax as apparent from GC-MS. The fuel contents in the explosives were 3.3-6.2% for ordinary waxes but 8.9-11.2% for synthetic waxes probably related to high melting and low melting points of the natural waxes and synthetic waxes. The results showed that IED's were not truly ANFO as reported earlier. The ethereal solutions of the waxes showed fluorescence but the excitation maxima and the fluorescence maxima were similar indicating the similarities of the hydrocarbons present with changes in molecular weights in the hydrocarbon fractions of the fuel.