A kinetic mechanism for predicting secondary organic aerosol formation from toluene oxidation in the presence of NOx and natural sunlight
A kinetic mechanism for predicting secondary organic aerosol formation from toluene oxidation in the presence of NOx and natural sunlight
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DOI：
10.1016/j.atmosenv.2007.04.025
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发表时间：
2007-10
影响因子：
5
通讯作者：
D. Hu;M. Tolocka;Qian-feng Li;R. Kamens
中科院分区：
文献类型：
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作者：
D. Hu;M. Tolocka;Qian-feng Li;R. Kamens
提出了一种预测甲苯光氧化生成二次有机气溶胶（SOA）的动力学机制。介绍了气溶胶的相化学，包括成核、气粒分配和粒相反应，以及甲苯及其降解产物的气相化学。根据北卡罗来纳州大学（University of North Carolina）270 m3双室外气溶胶烟雾室设施获得的实验数据对该机制进行了评估。该模型充分模拟了甲苯的衰减，一氧化氮（NO）到二氧化氮（NO2）的转化和臭氧的形成。它还提供了在15至300μgm−3的不同条件下SOA产生的合理预测。模拟气溶胶材料的形态表明，高达70%的气溶胶质量来自低聚物和聚合物取决于初始反应物浓度。由该机制预测的主要颗粒相物种是乙二醛低聚物、来自甲苯OH反应产物2-甲基-2，4-己二烯二醛的光解的烯酮低聚物、有机硝酸盐、甲基硝基苯酚类似物、C7有机过氧化物、酰基过氧硝酸盐和对于低浓度实验的不饱和羟基硝基酸。
A kinetic mechanism to predict secondary organic aerosol (SOA) formation from the photo-oxidation of toluene was developed. Aerosol phase chemistry that includes nucleation, gas–particle partitioning and particle-phase reactions as well as the gas-phase chemistry of toluene and its degradation products were represented. The mechanism was evaluated against experimental data obtained from the University of North Carolina (UNC) 270m3dual outdoor aerosol smog chamber facility. The model adequately simulates the decay of toluene, the nitric oxide (NO) to nitrogen dioxide (NO2) conversion and ozone formation. It also provides a reasonable prediction of SOA production under different conditions that range from 15 to 300μgm−3. Speciation of simulated aerosol material shows that up to 70% of the aerosol mass comes from oligomers and polymers depending on initial reactant concentrations. The dominant particle-phase species predicted by the mechanism are glyoxal oligomers, ketene oligomers from the photolysis of the toluene OH reaction product 2-methyl-2,4-hexadienedial, organic nitrates, methyl nitro-phenol analogues, C7 organic peroxides, acylperoxy nitrates and for the low-concentration experiments, unsaturated hydroxy nitro acids.