ratio are not the same. For the same U, 2-butanone/O2/Ar system
always has more oxygen than 3-buten-2-one/O2/Ar mixture. This
disturbs the comparison since oxygen plays a significant role in
determining the ignition delay times of these two oxygenated
fuels. However, when comparing the decomposition reactions of
both fuels at similar conditions, a logical conclusion can be drawn.
At 1250 K, the rate of decomposition of 2-butanone is 550 s1 compared
to 57.4 s1 for 3-buten-2-one. This remarkable difference in
reaction rates explains the longer ignition delay times for 3-buten-
2-one when testing stoichiometric mixtures since the decomposition
reaction affects the ignition delay times.