氢氧自由基与长链烷烃反应产物的气相色谱质谱检测初探

GC-MS Detection Study on the Products of Hydroxyl Radical and Long-Chain Alkanes Reaction

利用烟雾箱系统,以H_2O_2的紫外光解作为OH自由基来源,模拟OH与正十五烷和2,6,10-三甲基十二烷的反应,采用长链烷烃与OH自由基反应产物的Tenax管吸附采样-自动热解析-气相色谱-质谱联用(GC-MS)法分析,获得长链烷烃与OH反应的氧化产物信息,并对长链烷烃与OH的反应机制作初步探讨。

It is reported that the reaction products of volatile organic compounds （YOCs） with atmospheric oxidant （ O3 , OH, N03 , Cl, etc. ） are important sources of the secondary organic aerosol （ SOA） , which has great influence on the environmental quality. In this study, the OH radical was obtained using the photolysis of H202 under 224 nm UV light, and the reactions of OH with pentadecane, 2,6,10-trimethyl dodecane were con-ducted in a 5 m3 smoke chamber. In this paper, a method was established to analyze the products by Tenax tube adsorption sampling-automatic thermal desorption-gas chromatography-mass spectrometry （GC-MS）. The reaction mechanism of long chain alkanes with OH radical was discussed on the basis of the product information. The re-sults are believed to be helpful to understand the conversion process of the exhaust of diesel vehicles to SOA in the atmosphere.