title: Determination of emulsion explosives with Span-80 as emulsifier by gas chromatography-mass spectrometry.
abstract: A novel approach for identification and determination of emulsion explosives with Span-80 (sorbitol mono-oleate) as the emulsifier and their postblast residues by gas chromatography-mass spectrometry (GC-MS) has been developed. 24 kinds of emulsion explosives collected have been processed by transesterification reaction with metholic KOH solution and the emulsifier has turned into methyl esters of fatty acids. From the peak area ratios of their methyl esters, most of these emulsion explosives can be differentiated. In order to detect the postblast residues of emulsion explosives, the sorbitols in the emulsifier Span-80 obtained after transesterification reaction have been further derivatized by silylation reaction with N,O-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) containing 1% trimethylchlorosilane (TMCS) as the derivatizing reagent. The derivatization conditions were optimized and the derivatives were determined by GC-MS. The results showed that the silylation derivatives of sorbitol and it isomers, combined with hydrocarbon compounds and methyl esters of fatty acids, were the characteristic components for identification of the emulsion explosives. The established approach was applied to analyze the postblast residues of emulsion explosives. It has been found that the method was sensitive and specific, especially when detecting the derivatives of sorbitol and its isomers by GC-MS in selecting ion mode. The information of the characteristic components can help probe the origin of the emulsion explosives and providing scientific evidences and clues for solving the crimes of the emulsion explosive explosion.
authors.affiliation: Analytical & Testing Center of Beijing Normal University, Beijing 100875, China.
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: Tian
authors.forename: Jing
authors.initials: J
authors.lastname: Yu
authors.forename: Jia-Hong
authors.initials: JH
authors.lastname: Hu
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Meng-Xia
authors.initials: MX
authors.lastname: Xie
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiang-Feng
authors.initials: XF
authors.lastname: Wang
authors.forename: Hai-Ling
authors.initials: HL
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Han
mesh_terms: D045703:Emulsifying Agents / Q000032:analysis* / Q000737:chemistry; D053834:Explosive Agents / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006601:Hexoses / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry; D013012:Sorbitol / Q000032:analysis / Q000737:chemistry
chemical_list: D045703:Emulsifying Agents; D053834:Explosive Agents; D006601:Hexoses; D012989:Soil Pollutants; C018665:sorbitan monooleate; D013012:Sorbitol