Mechanistic and kinetic studies on OH-initiated atmospheric oxidation degradation of benzo[α]pyrene in the presence of O2 and NOx
Mechanistic and kinetic studies on OH-initiated atmospheric oxidation degradation of benzo[α]pyrene in the presence of O2 and NOx
复制标题
O2 和 NOx 存在下 OH 引发苯并[α]芘大气氧化降解的机理和动力学研究
DOI：
10.1016/j.chemosphere.2014.07.001
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发表时间：
2015-01-01
期刊：
影响因子：
8.8
通讯作者：
Wang, Wenxing
中科院分区：
文献类型：
--
作者：
Dang, Juan;Shi, Xiangli;Wang, Wenxing
大气中多环芳烃(PAHs)的降解可导致有毒的衍生物，这些衍生物有助于颗粒有机物的致癌潜力。本文旨在研究致癌风险指示剂苯并[α]芘(BaP)在OH作用下的氧化降解机理。进行了高精度的分子轨道计算，并讨论了所有可能的降解途径。将理论结果与已有的实验观测结果进行了比较。并对可能发生的二次反应进行了探讨。利用莱斯-拉姆斯佩格-卡塞尔-马库斯(RRKM)理论计算了关键步骤的速率常数。主要的降解产物有苯并[α]吡喃、硝基苯并[α]芘、苯并[α]芘-7，10-二酮以及烷基取代苯并三氢甲醛等开环产物。特别是，水在导致硝基苯并[α]芘形成的降解途径中起着重要的作用。这项工作对羟基引发的BaP的降解进行了全面的调查，并应有助于澄清其潜在的风险。(C)2014爱思唯尔有限公司。保留所有权利。
The degradation of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere can lead to toxic derivatives which contribute to the carcinogenic potential of particulate organic matter. This paper aimed to investigate the mechanism of the OH-initiated oxidation degradation of benzo[alpha]pyrene (BaP), a cancer risk indicator. High-accuracy molecular orbital calculations were carried out, and all of the possible degradation pathways were discussed. The theoretical results were compared with the available experimental observation. The possible secondary reactions were also investigated. The rate constants of the crucial elementary steps were evaluated by using the Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The dominant degradation products involve benzo[alpha]pyren-ol, nitro-benzo[alpha]pyrene, benzo[alpha]pyrene-7,10-dione as well as several ring-opened products such as alkyl substituted benzanthraldehyde et al. In particular, water plays an important role in the degradation pathways leading to the formation of nitro-benzo[alpha]pyrene. This work provides a comprehensive investigation of the OH-initiated degradation of BaP and should help to clarify its potential risk. (C) 2014 Elsevier Ltd. All rights reserved.