Temperature dependence of the yields of methacrolein and methyl vinyl ketone from the OH-initiated oxidation of isoprene under NOx-free conditions
Temperature dependence of the yields of methacrolein and methyl vinyl ketone from the OH-initiated oxidation of isoprene under NOx-free conditions
复制标题
无 NOx 条件下异戊二烯 OH 引发氧化反应生成异丁烯醛和甲基乙烯基酮的产率与温度的关系
DOI：
10.1016/j.atmosenv.2013.06.032
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发表时间：
2013
影响因子：
5
通讯作者：
P. Stevens
中科院分区：
文献类型：
--
作者：
M. Navarro;S. Dusanter;P. Stevens
在无NOx条件下，在与质谱仪耦合的石英反应室中，在303、323和343 K和1 atm下测量了来自OH引发的异戊二烯氧化的甲基丙烯醛（MAC）和甲基乙烯基酮（MVK）的产率。在303 ~ 343 K的温度下，测得的MAC和MVK产率分别约为9-11%和17 ~ 22%，与先前的研究结果一致。在303和323 K以及在343 K的MAC的实测产率的MAC和MVK的实测产率被合理地再现，以及使用显式异戊二烯氧化模型。然而，在343 K的MVK的实验产量被低估的模型，这表明MVK的温度依赖性源丢失。最近提出的几个补充异戊二烯氧化机制，包括1，6-和1，5-H变换异构化反应的异戊二烯基羟烷基过氧自由基，进行了测试，以确定这些机制是否可以解释所观察到的温度依赖性的产品收率。
Yields of methacrolein (MAC) and methyl vinyl ketone (MVK) from the OH-initiated oxidation of isoprene were measured under NOx-free conditions at 303, 323 and 343 K and 1 atm in a quartz reaction chamber coupled to a mass spectrometer. Measured yields of MAC and MVK were approximately 9–11% and 17−22%, respectively at temperatures between 303 and 343 K, in good agreement with previous studies. The measured yields of MAC and MVK, at 303 and 323 K as well as the measured yield of MAC at 343 K were reproduced reasonably well using an explicit model of isoprene oxidation. However, the experimental yields of MVK at 343 K were underestimated by the model, suggesting that a temperature dependent source of MVK was missing. Several recently proposed additions to the isoprene oxidation mechanism, including 1,6- and 1,5-H shift isomerization reactions of isoprene-based hydroxyalkyl peroxy radicals, were tested in order to determine if these mechanisms can explain the observed temperature dependence of the product yields.