Experimental and kinetic modeling study of the oxidation of methyl hexanoate

The oxidation of methyl hexanoate has been studied experimentally in a jet-stirred reactor at 10 atm and a constant residence time of 1 s, over the temperature range 500-1000 K and for fuel-Jean to fuel-rich conditions. Concentration profiles of reactants, stable intermediates, and final products have been obtained by sonic probe sampling followed by online and offline GC analyses. The oxidation of methyl hexanoate under these conditions showed the three regimes of oxidation well-known for large hydrocarbons, namely cool flame, negative temperature coefficient, and high temperature oxidation. It was modeled using a detailed chemical kinetic reaction mechanism (435 species and 1875 reversible reactions). This mechanism was validated by comparing the present experimental results to the simulations. The main reaction pathways involved in methyl hexanoate oxidation were delineated computing rate of formation and consumption. The present results show a strong similitude with the oxidation of n-alkanes.