Theoretical study of the hydrogen abstraction reactions from substituted phenolic species

Abstract

The growing interest in the use of bio-oils requires a detailed understanding of its combustion chemical kinetics. Bio-oils contain a large variety of oxygenated organic species, in which substituted phenolic compounds are among the most significant fractions. Hence, accurate assessment of key reaction rate constants and systematically investigated the structural effect on the reactivity are critical. This work reports a systematic theoretical study of the hydrogen abstraction reactions from phenol, anisole,o-guaiacol,m-guaiacol, andp-guaiacol, which are considered as reference components in bio-oil surrogates. The hydrogen abstraction reactions by five different radicals (H/CH3/O(3P)/OH/HO2) are investigated atROCBS-QB3//M06-2X/cc-pVTZ level. The high-pressure limit rate constants are computed via transition state theory with Eckart tunnelling and the 1-D hindered rotor approximation. Comparisons of site-specific hydrogen abstractions from the studied species with other related species are performed to understand the effects of the aromatic ring and side-chain substituent on hydrogen abstractions.