珠三角城市群PM2.5和O3污染特征及VOCs组分敏感性分析

系统分析了珠三角城市群PM_2.5、O₃和挥发性有机物（VOCs）的污染特征，并筛选出对二次有机气溶胶（SOA）和O₃影响较大的敏感性组分。结果显示:珠三角城市群PM_2.5和O₃浓度的季节变化具有明显差异，PM_2.5和O₃分别在1月和10月出现浓度最高值。珠三角城市群VOCs主要以烷烃为主，占比为64.2%，其次为芳香烃和烯烃，含量较高的组分为丁烷、异戊烷、异丁烷和环己烷。SOA生成潜势贡献主要以芳香烃为主，占比为78.5%，其中甲苯、间，对-二甲苯和乙苯的SOA生成潜势最大。O₃生成潜势主要以烯烃为主，占比为42.3%，其次为芳香烃（34.2%）和烷烃（23.5%），其中丙烯、异戊二烯和1-丁烯的O₃生成潜势最大。为有效缓解珠三角城市群PM_2.5和O₃污染，建议优先对机动车尾气、溶剂挥发、涂料使用和石化行业的VOCs敏感组分进行控制。

POLLUTION CHARACTERISTICS OF PM2.5 AND O3 IN THE PEARL RIVER DELTA AND THE SENSITIVITY ANALYSIS OF VOCs COMPONENTS

The pollution characteristics of PM_2.5, O₃, and volatile organic compound (VOCs) were analyzed in the Pearl River Delta, China. The sensitive components with greater influence on the formation of secondary organic aerosol (SOA) and O₃ were also screened. The results indicated that there was obvious difference in seasonal variation of PM_2.5 and O₃ concentrations in the Pearl River Delta. The concentrations were the highest in January and October for PM_2.5 and O₃, respectively. The VOCs was dominated with alkane, accounting for 64.2% of the total VOCs mass content, followed by aromatics and alkene. The components with the highest content were butane, isopentane, isobutane and cyclohexane. The SOA generation potential was mainly contributed by aromatics, accounting for 78.5% of the total generation potential. The components with the highest SOA generation potential were toluene, m, p-xylene and ethylbenzene. The O₃ generation potential was mainly contributed by alkene, accounting for 42.3% of the total generation potential, followed by aromatics (34.2%) and alkane (23.5%). The components with higher O₃ generation potential were propylene, isopentadiene and 1-butene. It was suggested that priority control should be given to the sensitive components of VOCs emitted from vehicle exhaust, solvent volatilization, paint usage, and petrochemical industry to alleviate the PM_2.5 and O₃ pollution effectively in the Pearl River Delta.