機車排放物中多苯環芳香烴之探討

Determination of PAHs in Motorcycle's Exhaust

李偉平(Wai-Ping Lee) ； 林建揚(Chien-Yang Lin)

《化學》 51卷3期 (1993/09) Pp. 287-298

https://doi.org/10.6623/chem.1993030

摘要

多苯環芳香烴(Polycyclic Aromatic Hydrocarbons, PAHs)，已被證實在臨床上具有致癌性與發生腫瘤病變，因此在環境中之分佈引起相當重視。多苯環芳香烴大部份為碳氫化合物燃燒不完全過程之產物。由於石油燃料在目前仍為主要的能源，一般相信石油燃料在燃燒過程中所產生之污染物應為多苯環芳香烴之主要來源。本研究結合管柱色層分析法，氣相色層分析儀(GC)與氣相色層分析儀/質譜儀(GC/MS)等分析方法，探討機車排放煙管內積垢之有機化合物分佈，藉以了解機車排放物中多苯環芳香烴之污染情形；管柱色層分析法係使用玻璃管柱，以矽膠作為填充劑，並且以正戊烷及二氯甲烷之混合溶劑依序溶析，將樣品中成份，依其化學種類分成脂肪族氫化合物(A-1)、中性多苯環芳香烴(A-3)及含氮多苯環芳香烴(A-3)等三個族群，再以GC及GC/MS對各個族群作進一步分析與鑑定，以了解族群之成份，並以此結果作為管柱對實際樣品分離效率之評估；此外以同一機車所用之汽油依相同之分析方法做分離，與煙管內之積垢作一比較，則發現汽油在機車引擎室燃燒後，會有多苯環芳香化合物及其衍生物的產生。

並列摘要

Polycyclic aromatic hydrocarbons, PAHs, are specified as chemical carcinogens, and very much attention is paid to their distribution in the environment. Nowaday, petroleum fuel is the major source of energy supply, so the vast use of petroleum fuel could be a major source of PAHs. This paper describes the combination of column chromatography, gas chromatography (GC) and gas chromatography/Mass spectrometry (GC/MS) to find out the distribution of organic compounds, especially the PAHs, in the exhaust of a motorcycle. Column chromatography using silica gel as the packing material was developed for the separation of the components of motorcycle's exhaust into aliphatics (A-1), neutral PAHs (A-2) and nitro-PAHs (A-3) according to the chemical class they belong to. The eluent system is based on a stepwise gradient of dichloromethane in n-Pentane. The components of each group were identified by GC and GC/MS. Evluation of the efficiency of column chramatography was made by comparing the result of the analysis of the real samples. The identified components of gasoline and that of the motorcycle's exhaust show that a great amount of PAHs and alkylated derivatives are formed after the combustion of gasoline in the motorcycle's engine.