热脱附-气相色谱-质谱法测定机动车尾气中气相烷烃和多环芳烃含量  

Determination of gas phase alkanes and polycyclic aromatic hydrocarbons in vehicle exhaust by thermal desorption-gas chromatography-mass spectrometry

作　　者：李光辉 蒋斌 周文钦 刘俊文 郑君瑜 王伯光 刘永林 张展毅 LI Guanghui;JIANG Bin;ZHOU Wenqin;LIU Junwen;ZHENG Junyu;WANG Boguang;LIU Yonglin;ZHANG Zhanyi(Institute for Environmental and Climate Research,Jinan University,Guangzhou,511443,China;Guangdong-HongkongMacao Joint Laboratory of Collaborative Innovation for Environmental Quality,Guangzhou,511443,China;State Key Laboratory Organic Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Science,Guangzhou,510640,China;Hangzhou Puyu Technology Development Co.,Ltd.,Hangzhou,311305,China)

机构地区：[1]暨南大学环境与气候研究院,广州511443 [2]粤港澳环境质量协同创新联合实验室,广州511443 [3]杭州谱育科技发展有限公司,杭州311305 [4]中国科学院广州地球化学研究所,有机地球化学国家重点实验室,广州510640

出　　处：《环境化学》2023年第6期1981-1991,共11页Environmental Chemistry

基　　金：国家重点研发计划项目(2018YFC0213904);国家自然科学基金(41977178);广东省省级科技项目(2017B030314057);广东省环境资源利用与保护重点实验室开放基金(KLEPRU-201809)资助.

摘　　要：采用热脱附结合气相色谱质谱联用仪(TD-GC-MS),建立了机动车尾气中30种正构烷烃(C7—C36)、2种支链烷烃(植烷、姥鲛烷)和19种多环芳烃(PAHs)的分析方法.利用Tenax-TA吸附管采集机动车尾气样品,加入定量的内标物;热解吸后经HP-5色谱柱分离、在选择性离子监测(SIM)模式下用GC-MS检测,内标法定量.为提高方法的灵敏度、精准度等指标,优化了脱附管解吸温度、解吸时间,冷阱捕集温度、脱附温度、脱附时间和GC-MS分析条件.结果表明,51种目标物在1—50 ng范围内线性良好,相关系数(R^(2))均大于0.994,方法检出限为0.05—0.48μg.m^(-3),定量下限为0.20—1.90μg.m^(-3),在低、中、高的3个加标水平下的回收率为86.7%—119.9%,相对标准偏差(RSD,n=7)为1.0%—5.7%,将其应用于轻型柴油车尾气样品的测定,共检测出44种目标物,包括28种正构烷烃、2种支链烷烃、14种PAHs.该方法简便快速、稳定灵敏、准确度高,可满足机动车尾气中烷烃和PAHs的测定需求.An analytical method was established for the determination of 30 n-alkanes(C7—C36),2 branched alkanes(phytane,pristane)and 19 polycyclic aromatic hydrocarbons(PAHs)in vehicle emission by thermal desorption-gas chromatography-mass spectrometry(TD-GC-MS).Samples were collected by Tenax-TA adsorption tube,and the internal standard was added.After desorbed by thermal desorption,the analytes were determined by GC-MS in selected ion monitor(SIM)mode after separation by HP-5 column,and quantified by internal standard method.In order to improve the sensitivity and precision of method,various parameters such as desorption temperature and time of adsorption tube;cold trap,capture temperature of cold trap,and the analysis conditions of GC-MS were optimized.Results showed that the calibration curves for 51 compounds exhibited good linearity in the concentration range of 1-50 ng,with all the correlation coefficients(R^(2))morn than 0.994.The limits of detection and the limits of quantification were in the ranges of 0.05—0.48μg·m^(-3) and 0.20—1.90μg·m^(-3),espectively.The average recoveries at low,medium and high spiked levels ranged from 86.7%to 119.9%with the relative standard deviations(RSDs,n=7)of 1.0%—5.7%.The method was applied to the determination of alkane and PAHs in the exhaust of light diesel vehicle.A total of 44 targets were detected,including 28 n-alkanes,14 PAHs and 2 branched alkanes.The method was simple,rapid,stable,sensitive and accurate,and was suitable for the determination of alkane and PAHs in motor vehicle emissions.

关 键 词：烷烃 多环芳烃 半 中等挥发性有机物 机动车尾气 气质联用仪 热脱附 

分 类 号：X831[环境科学与工程—环境工程] O657.63[理学—分析化学]