Ab initio kinetics predictions for H-atom abstraction from 2-butanone by H˙ and C˙H3 and the subsequent unimolecular reactions

2-butanone was recently identified as a promising gasoline biofuel. Its kinetic modeling requires high-level kinetic predictions of key reactions to reduce the uncertainty in the reaction model. The present work provides rate constants for hydrogen abstraction from 2-butanone by H˙ and C˙H3. Subsequent unimolecular reactions on the 2-butanoyl radical potential energy surface were studied using RRKM/Master Equation. The updated rate constants deviate from previous predictions by up to two orders of magnitude.The potential energy surfaces computed for hydrogen abstraction and β-scission were connected by using rovibrationally excited 2-butanoyl radicals as reactants of the β-scission reaction network. The energy distributions of these excited radicals were computed from the preceding hydrogen abstraction reactions. Though at engine-relevant conditions rovibrationally excited 2-butanoyl radicals were found to be negligible, kinetic modeling of flames at very low pressures and high temperatures would require to include reactions of excited fuel radicals. The reported rate constants significantly change the ignition delay predictions, emphasizing the need for more accurate predictions for novel fuels.