汽车尾气中多环芳烃(PAHs)成分谱图研究

采集并测定了不同型号、油品、里程数的汽车尾气中14种多环芳烃,对分析结果归一化处理后确定其多环芳烃成分谱图.研究表明,汽车在30rmin内排放的14种PAHs总浓度为41.53～121.1μg/m³;其中苯并(a)蒽(BaA)浓度最大,占总量的33.3%;萘(Naph)、苯并(ghi) (Bghip)、茚(1,2,3-cd)芘(In)分别为16.8%、12.9%和12.1%.相同里程数的柴油车排放PAHs总量大于汽油车;除BaA和Naph,柴油车主要排放苊(Ac)、芴(Fluor)、Bghip和In,而汽油车主要排放Bghip、In、苯并(k)荧蒽(BkF).柴油车排放3环PAHs的量大于汽油车,但5～6环PAHs的排放量小于汽油车;随着汽车里程数的增加,PAHs(特别是荧蒽(Flur)、芘(Py)、苯并(a)芘(BaP)、Bghip)的排放总量增加.

Research on PAHs Fingerprints of Vehicle Discharges

Air samples of 14 PAHs were collected from vehicle discharges of different types, oils, and mileages and analyzed by HPLC. It showed that the total PAHs discharged from the vehicle in 30 minutes were 41.53-121.1 micrograms/m3, among which, BaA was the most predominant, about 33.3%, followed by Naphthalene, Benzo (ghi) pyrene and In (1,2,3-cd) pyrene, about 16.8%, 12.9% and 12.1%, respectively. Diesel vehicle discharged more total PAHs compared to gasoline vehicle. The two vehicles all exhausted much BaA and Naph, however diesel vehicle mainly emitted Ac, Fluor, Bghip, In, while gasoline discharged mainly Bghip, In, BkF. PAHs with five or more rings in gasoline discharges were relatively higher than those in diesel discharges, however to 3-ring PAHs, diesel vehicle produced more than gasoline vehicle. As for vehicle of different mileage, there was a clear increase for almost all PAHs, especially Flur, Py, BaP, Bghip.