Kinetic investigations on the high- and low-temperature chemistry of ethyl acetate

Abstract

Although esters are discussed and used as biodiesel fuels, the fundamental understanding of their combustion, especially for ethyl esters, is still deficient. To improve both the experimental database and theoretical knowledge, ignition delay times were measured down to 835 K and quantum chemical calculations were performed for thermochemical properties and reaction rates of ethyl acetate and crucial intermediates. The ignition delay times measured in a shock tube and a rapid compression machine complement existing data in the literature and serve as validation targets for kinetic modeling. The experiments were conducted at 20 and 40 bar for stoichiometric and undiluted mixtures. No negative temperature coefficient (NTC) behavior was observed at these conditions. The quantum mechanical calculations are aimed at a better understanding of the low-temperature chemistry and the influence of the ester moiety. The calculations of the reaction kinetics of C˙H2COOH and its interaction with molecular O2 resolve uncertainties for rates that appeared to be sensitive during the model development.