High temperature branching ratio of acetaldehyde +OH reaction
نویسندگان
چکیده
The reaction of acetaldehyde (CH3CHO) with hydroxyl radicals (OH) plays an important role in atmospheric and combustion chemistry. low-temperature chemistry this has been studied widely the literature. However, branching at high temperatures is not well known. Aiming to deduce ratio CH3CHO + OH, measurements were carried out a shock tube by introducing deuterium into chemical system. Overall rate coefficients for OH reactions (CH3CHO), acetaldehyde-2,2,2-d3 (CD3CHO), acetaldehyde-d4 (CD3CDO) measured over temperature range 950-1300 K 1.5–3.0 bar. In addition, acetone (CH3C(O)CH3) acetone-d6 (CD3C(O)CD3) kinetic isotopic effect H-abstraction methyl site. can be represented following Arrhenius expressions (cm3/molecule/s): k1(CH3CHO+OH)=1.29×10?10exp(?1996.5KT) k2(CD3CHO+OH)=1.06×10?10exp(?2151.9KT) k3(CD3CDO+OH)=1.18×10?10exp(?2554.1KT) k4(CH3COCH3+OH)=7.15×10?11exp(?2695.7KT) k5(CD3COCD3+OH)=6.02×10?11exp(?3130.5KT) contrast chemistry, our results indicate that from site fraction channel ? 65%. On per H atom basis, however, aldehydic group faster than even temperatures.
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ژورنال
عنوان ژورنال: Proceedings of the Combustion Institute
سال: 2021
ISSN: ['1873-2704', '1540-7489']
DOI: https://doi.org/10.1016/j.proci.2020.07.048