机动车尾气中的多环芳烃类污染物分析及监测技术创新

Innovations in the analysis and monitoring of polycyclic aromatic hydrocarbon pollutants in vehicle exhaust

对机动车尾气污染物中危害性最大的多环芳烃类(PAHs)进行了表征和量化。采集了车辆在加速、减速、匀速和怠速等不同行驶工况下的尾气样品,通过反相高效液相色谱法(HPLC)进行成分定量分析。结果表明,气相中较低分子量(2~3环)的多环芳烃浓度高于固相中的多环芳烃浓度,而高分子量(5~6环)的多环芳烃浓度在固相中富集。双环、三环和四环多环芳烃的总量占气相多环芳烃总质量浓度的87%,五元环和六元环多环芳烃大约占多环芳烃总含量10%和4%。相比之下,二环和三环多环芳烃在固相多环芳烃中的比例有所下降。三、四和五元多环芳烃在固相中具有绝对优势,分别占柴油和汽油车尾气中多环芳烃总量的89%和81%。

Polycyclic aromatic hydrocarbons(PAHs)which are the most harmful pollutants in motor vehicle ex⁃haust were characterized and quantified.The tail gas samples of vehicles under different driving conditions such as acceleration,deceleration,uniform speed and idle speed were collected and analyzed quantitatively by reverse phase high performance liquid chromatography(HPLC).The results show that the concentration of polycyclic aro⁃matic hydrocarbons with low molecular weight(2~3 rings)in the gas phase is higher than that in the solid phase,while the concentration of polycyclic aromatic hydrocarbons with high molecular weight(5~6 rings)is enriched in the solid phase.The total amount of bicyclic,tricyclic and tetracyclic polycyclic aromatic hydrocarbons accounts for 87%of the total concentration of gas-phase polycyclic aromatic hydrocarbons,and five membered and six mem⁃bered polycyclic aromatic hydrocarbons account for about 10%and 4%of the total content of polycyclic aromatic hydrocarbons.In contrast,the proportion of bicyclic and tricyclic PAHs in solid PAHs decreases.Three,Four and five membered polycyclic aromatic hydrocarbons have absolute advantages in solid phase,accounting for 89%and 81%of the total polycyclic aromatic hydrocarbons in diesel and gasoline vehicle exhaust,respectively.