Kinetics and thermochemistry of cyclohexadienes reactions with hydroxyl radicals
نویسندگان
چکیده
Cyclohexadienes (CHDs) are important intermediates in the pyrolysis and oxidation of many C6 cyclic hydrocarbons. Under combustion relevant conditions, these dienes may either eliminate H2 directly or lose H atoms sequentially to produce first aromatic ring, i.e., benzene. This is one major reaction pathways for formation benzene from Despite its importance PAH soot process, chemistry CHD has attracted less attention scientific community. In this work, we have investigated hydrogen abstraction reactions 1,3- 1,4-CHD by OH radicals using a shock tube UV laser absorption over temperature range 900 – 1100 K pressures ? 1 3 atm. Reaction kinetics was followed monitoring near 307 nm. At high temperatures, both isomers CHDs found exhibit comparable reactivity with radicals. These show weak positive dependence. Measured rate coefficients can be represented following Arrhenius expressions units cm3 molecule?1 s ? 1: k1(1,3?CHD+OH)=1.76×10?10exp(?1761KT)k2(1,4?CHD+OH)=2.23×10?10exp(?1813KT) To gain further insights into reactions, various ab initio methods were employed compute thermochemical data. study reports high-temperature kinetic data cyclohexadienes which will beneficial improve performance models
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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.2020.06.259