热脱附-气相色谱-质谱法判定纵火案件燃烧残留物中的汽油成分  

Identify Residual Gasoline Components in Combustion Residues in Arson Site with ATD-GC-MS

作　　者：王力春[1] 石银涛[1] 鲁蕴甜 王兵 WANG Lichun;SHI Yintao;LU Yuntian;WANG Bing(Material Evidence Identification Center of Chongqing Public Security Bureau,Chongqing400021,China;Chongqing Jiulongpo Ecological Environment Monitoring Station,Chongqing401329,China;Criminal Technology Office of Yubei District Branch of Chongqing Public Security Bureau,Chongqing401120,China)

机构地区：[1]重庆市公安局物证鉴定中心,重庆400021 [2]重庆市九龙坡区生态环境监测站,重庆401329 [3]重庆市公安局渝北区分局刑事科学技术室,重庆401120

出　　处：《理化检验（化学分册）》2020年第11期1193-1200,共8页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：重庆市公安局科技攻关计划项目(G2016-02)。

摘　　要：建立一种用热脱附-气相色谱-质谱法(ATD-GC-MS)分析纵火现场燃烧残留物成分,用目标化合物法判定其中是否有汽油成分的方法。取92#汽油标准品、25种常见空白样品和加标空白样品(全实木木地板、闹钟外壳、文件夹、普通棉絮和塑料脸盆)进行燃烧试验,燃烧残留物用Tenax TA吸附管吸附,用二阶脱附模式解吸附,用气相色谱-质谱法分析。采用目标化合物法将样品燃烧残留物中4类化合物[烷烃类特征离子碎片质荷比(m/z)57,85、芳烃类m/z 91,105,119、茚满类m/z 117,131和萘类m/z 128,142,156]的总离子流(TIC)色谱图的谱图中各化合物类别、相对丰度与汽油标准品及空白样品燃烧残留物进行比对来判定样品中是否含有汽油成分。结果显示:汽油燃烧后呈现轻组分相对丰度减小、重组分相对丰度增加、保留时间整体后移的规律;空白样品燃烧后可检出与汽油相同的组分,但组分的类别及相对丰度与汽油标准品燃烧残留物相比有差异;加标空白样品燃烧残留物中均检出汽油组分,其相对丰度和燃烧规律均与汽油标准品燃烧残留物的一致。A method was developed for the analysis of the components of combustion residues in arson site by ATD-GC-MS,in order to determine the presence of gasoline components with target compound method.The combustion test was made on 92#gasoline standard,the 25common blank samples and blank spiked samples(all solid wood floor,alarm clock shell,folder,ordinary cotton wadding and plastic washbasin).The combustion residue obtained was adsorbed by Tenax TA adsorption tube and desorbed by second-order desorption mode,and then separated and identified by GC-MS.The category and relative aboundance of the 4classes composed of compound(alkanes m/z 57,85,aromatics m/z 91,105,119,indene and naphthalene m/z 117,131and naphthalene m/z 128,142,156)in combustion residues of the sample in the TIC chromatogram were compared with those of combustion residues of gasoline standard and blank sample by the target compound method,thus to determine whether there was gasoline in the sample.The results showed that:A combustion law was presented after combustion of gasoline that the relative abundance of light components decreased,the relative abundance of heavy components increased,and the retention time moved backward;the same components could be detected in blank samples after combustion,but the category and relative abundance of components were different from those of combustion residues of gasoline standard;gasoline components were detected in combustion residues of spiked blank samples,and their relative abundance and combustion law were consistent with those of combustion residues of gasoline standard.

关 键 词：二阶热脱附 气相色谱-质谱法 目标化合物法 汽油成分 燃烧残留物 

分 类 号：O657.63[理学—分析化学]