Speciation and Photochemical Reactivity of Airborne Volatile Organics in Ozone Non-attainment Region -- A Case Study in Southern Taiwan

摘要

This research investigates the profiles of airbome volatile organic compounds (VOCs) in an ozone non-attainment region in southern Taiwan. Ozone and PM_(10) episodes occurred frequently in autumn and winter seasons basin widely. Field measurements had been conducted to take air sample with canisters at four air monitoring stations. There are 55 VOCs species, including anthorogenic and biogenic sources, quantified by GC/MS. Field measurements were implemented in cold seasons since 1997. Field measurement data indicate that the daily average concentrations of total VOCs were 87.3 ～ 233.7 mug /m~3 at different sites. The values of mass fraction for paraffin, oleffin and aromatic VOCs at these sites were 28 ～ 47%, 7 ～ 12%, and 41 ～ 52%, respectively. Toluene is the dominant species among the VOCs and is followed by isopentane, n-butane, and 1,2,4-trimethylbenzene. The photochemical reactivity of airbome VOCs was also evaluated by the index of maximum incremental reactivity (MIR).