Energy & Fuels, Vol.32, No.7, 7652-7659, 2018
Theoretical Studies on Isomerization and Decomposition Reactions of 2-Methyl-1-butanol Radicals
2-Methyl-l-butanol (2M1B) is a favorable candidate of substitute fuels characterized with high energy density and low hygroscopicity. 2M1B radicals, which are the products of H-abstraction reactions of 2M1B, and their isomerization and decomposition reactions play a cardinal impact on the distribution of combustion products. In this work, the primary isomerization and decomposition reaction channels of 2M1B radicals were investigated by using QCISD(T)/CBS//M062x/cc-pVTZ and CBS-QB3 method, respectively. The accurate phenomenological temperature- and pressure-dependent rate constants covering temperatures of 250-2500 K and pressures from 1 x 10(-3) to 1 x 10(3) bar along with high-pressure limit rate constants for these channels were computed by solving the RRKM/master equation. The calculations revealed that the isomerization reaction of RC2 -> RC6 has the highest energy barrier among these reactions, while the decomposition reaction RC6 -> CH3CH2CHCH3 + CH2O has the lowest energy barrier. Furthermore, the computed rate coefficients were also validated by using the previous pyrolysis experiment. The modeling results reproduce the experimental results satisfactorily. The current work not only provides reasonable kinetic data for the development of 2M1B combustion models but also lays a foundation to extend the kinetic mechanisms of alcohol with a longer chain.