The effects of bath gas and NOx addition on n-pentane low-temperature oxidation in a jet-stirred reactor

The oxidation of n-pentane (C5H12) in different bath gases (He, Ar, CO2) and in Ar with NO2 or NO addition has been studied in a jet-stirred reactor at 107 kPa, temperatures between 500 1100 K, with a fixed residence time of 2.0 s, under stoichiometric conditions. Four different quantification diagnostics were used: gas chromatography, chemiluminescence NOx analyzer, continuous wave cavity ring-down spectroscopy, and Fourier transform infrared spectroscopy. The results showed that the onset temperature of the fuel reactivity was the same (575 K) regardless of the type of bath gases. Although the low-temperature fuel oxidation window was not affected by the type of bath gas, the n-pentane conversion was slightly larger when diluted in Ar through the negative temperature coefficient (NTC) region (625-725 K). Above 800 K, the reactivity according to the diluent was in the order CO2 > Ar > He. In the presence of NO2 or NO, it is found that the consumption rate of n pentane exhibited a different trend below 70...