Experimental and Theoretical Study of Reactions of OH Radicals with Hexenols: An Evaluation of the Relative Importance of the H-Abstraction Reaction Channel

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• 作者：Yanbo Gai ; Xiaoxiao Lin ; Qiao Ma ; Changjin Hu ; Xuejun Gu ; Weixiong Zhao ; Bo Fang ; Weijun Zhang ; Bo Long ; Zhengwen Long
• 刊名：Environmental Science & Technology
• 出版年：2015
• 出版时间：September 1, 2015
• 年：2015
• 卷：49
• 期：17
• 页码：10380-10388
• 全文大小：481K
• ISSN：1520-5851

文摘

C6 hexenols are one of the most significant groups of volatile organic compounds with biogenic emissions. The lack of corresponding kinetic parameters and product information on their oxidation reactions will result in incomplete atmospheric chemical mechanisms and models. In this paper, experimental and theoretical studies are reported for the reactions of OH radicals with a series of C6 hexenols, (Z)-2-hexen-1-ol, (Z)-3-hexen-1-ol, (Z)-4-hexen-1-ol, (E)-2-hexen-1-ol, (E)-3-hexen-1-ol, and (E)-4-hexen-1-ol, at 298 K and 1.01 脳 10<sup>5sup> Pa. The corresponding rate constants were 8.53 卤 1.36, 10.1 卤 1.6, 7.86 卤 1.30, 8.08 卤 1.33, 9.10 卤 1.50, and 7.14 卤 1.20 (in units of 10<sup>鈥?1sup> cm<sup>3sup> molecule<sup>鈥?sup> s<sup>鈥?sup>), respectively, measured by gas chromatography with a flame ionization detector (GC-FID), using a relative technique. Theoretical calculations concerning the OH-addition and H-abstraction reaction channels were also performed for these reactions to further understand the reaction mechanism and the relative importance of the H-abstraction reaction. By contrast to previously reported results, the H-abstraction channel is a non-negligible reaction channel for reactions of OH radicals with these hexenols. The rate constants of the H-abstraction channel are comparable with those for the OH-addition channel and contribute >20% for most of the studied alcohols, even >50% for (E)-3-hexen-1-ol. Thus, H-abstraction channels may have an important role in the reactions of these alcohols with OH radicals and must be considered in certain atmospheric chemical mechanisms and models.