2 - 乙氧乙醇的大气光氧化:糖醇的自氧化化学
Hongmin Yu1, Kristian H Møller2, Reina S Buenconsejo3
1Division of Geological and Planetary Sciences, California Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States.
The journal of physical chemistry. A
|November 7, 2023
概括
这项研究显示,2-乙氧乙醇 (2-EE) 容易发生自氧化,形成高氧化分子 (HOM). 这一途径对从挥发性有机化合物 (VOC) 中形成二次有机气溶 (SOA) 有意义.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
背景情况:
- 甘乙烯,包括2-乙氧乙醇 (2-EE),是消费品中常见的挥发性有机化合物 (VOC).
- 自氧化是一种已知的大气路径,形成高氧化有机分子 (HOM),是二次有机气溶 (SOA) 的前体.
研究的目的:
- 为了研究由基 (OH) 基启动的2-EE的气相光氧化.
- 阐明自氧化途径在2-EE氧化和HOM形成中的作用.
主要方法:
- 使用了实验室研究和计算建模的组合.
- 在不同度的氧基 (HO2) 下分析了光化学反应.
主要成果:
- 从双分子和自氧化途径中确定了氧化产物.
- 关键反应的估计速率系数和产品分支比.
- 发现2-EE过氧基 (RO2) 迅速经历H转移过程,与双分子反应竞争.
结论:
- 2-EE的自氧化是显著的,在典型的城市大气条件下有助于HOM的形成,特别是在降低的氧化 (NOx) 水平和高温下.
- 这项研究解决了从挥发性化学产品 (VCPs) 排放的有氧VOC中SOA形成的知识差距.
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