邯郸市秋季大气挥发性有机物污染特征

大气中VOCs（volatile organic compounds，挥发性有机物）是形成O₃和二次有机气溶胶的重要前体物.通过对2017年10月1-31日邯郸市秋季环境空气中56种VOCs污染物进行在线监测，结合PM_2.5、O₃、NO_x等污染物质量浓度和气象数据，分析了邯郸市VOCs质量浓度水平、时间变化特征、化学反应活性和主要来源.结果表明:邯郸市ρ（VOCs）变化范围较大，为49.1~358.4 μg/m3，平均值为（102.2±45.8）μg/m3，VOCs的主要组分为烷烃和芳烃.ρ（VOCs）与ρ（PM_2.5）、ρ（NO_x）均有很强的相关性，相关系数分别为0.8和0.7；而ρ（NO_x）与ρ（O₃）呈明显的负相关性，相关系数为-0.7.邯郸市VOCs中各类组分化学反应活性大小依次为烯烃>芳烃>烷烃>炔烃，并且国庆期间（10月1-7日）VOCs化学反应活性小于非国庆期间（10月8-31日），烯烃和芳烃对O₃的产生占主导地位.应用主因子分析法对邯郸市VOCs来源进行解析发现，溶剂使用和燃料挥发源、汽油车排放源、工业源、柴油车排放源和燃烧源是VOCs的主要来源，其方差贡献率分别为36.7%、15.5%、8.0%、6.6%、5.1%.研究显示，减少邯郸市大气中ρ（VOCs）应以控制溶剂使用和燃料挥发源、交通排放源（汽油车排放源和柴油车排放源）为主. 

Characteristics of Volatile Organic Compounds in Autumn in Handan City, China

Volatile organic compounds (VOCs) are important precursors for the formation of ozone and secondary organic aerosols. In recent years, ozone pollution became notably serious in many cities of China. It is important to understand the characteristics and chemical reactivity of the VOCs. This study used on-line observation data of 56 VOCs species in Handan City in October 2017, as well as PM_2.5, O₃, NO_x and meteorological data to analyze the pollution characteristics, temporal variations, chemical reactivity and sources apportionment of VOCs. The results showed that the concentrations of VOCs had a wide range from 49.1 to 358.4 μg/m3, and the average was (102.2±45.8) μg/m3. Alkanes and aromatics were the most abundant components. We also found that the concentrations of VOCs had good correlation with those of PM_2.5 and NO_x, with correlation coefficients of 0.8 and 0.7, respectively. NO_x and O₃ had negative correlation with correlation coefficient of -0.7. The chemical reactivity of VOCs in Handan City was alkene > aromatic > alkane > alkyne. Chemical reactivity on the National Days (Oct.1st-7th) was less than non-holiday period (Oct.8th-31st). Alkenes and aromatics dominated ozone formation. The principal component analysis showed that the major sources of VOCs were solvent use and fuel volatilization, gasoline vehicle emissions, industrial production, diesel vehicle emissions and combustion source, and their variance contributions were 36.7%, 15.5%, 8.0%, 6.6% and 5.1% respectively. The research shown that control of VOCs should be mainly reduced by controlling solvent use and fuel volatilization, traffic emission (gasoline vehicle emissions and vehicle emissions) in Handan City.