The identification and quantification of ketohydroperoxides and derived species produced during fuel low-temperature oxidation

Abstract

Since 2010, photoionization mass spectrometry (PI-MS) coupled to jet-stirred reactor (JSR) has allowed to make notable progress in the detection and quantification of ketohydroperoxides, the key species for engines autoignition and fuel low-temperature oxidation. Significant advances in the understanding of the chemistry related to ketohydroperoxides has also followed the simultaneous detection of carboxylic acids and diones. Recent work has shown that PhotoElectron PhotoIon COincidence (PEPICO) technique combined with first principle computations, consisting in the determination of adiabatic ionization energies and the Franck-Condon envelope of the photoionization spectra, can be applied for identifying isomers through the energy analysis of the correlated photoelectron during fuel low-temperature oxidation. Using this last technique has also helped refining ketohydroperoxide quantification though a better understanding of their fragmentation pattern.