Chemical Interpretation on the Multi-Stage Oxidation of Diethyl Ether

Multi-stage ignition and/or double NTC(negative temperature coefficient)behavior resulted from the low-temperature oxidation of ether compounds are still not clearly explained.We have investigated the oxidation mechanism of a stoichiometric DEE(diethyl ether)/air mixture by using a micro flow reactor with a controlled temperature profile to see the detail of low-temperature weak flame structure.The simulation was also performed to understand the chemical kinetics mechanism of observed weak flame structure.Chemiluminescence measurement showed separated weak flame in the temperature range of 600 K-800 K.The simulation also qualitatively reproduced this separated weak flame,and showed four peak of heat release.From the reaction flow analysis,it was found that(1)O-O bond scission reaction of keto-hydroperoxide produced by DEE,(2)O-O bond scission reaction of CH3O2H,CH3CO3H,and C2H5O2H,(3)O-O bond scission reaction of H2O2,and(4)H+O2=O+OH are key chain branching reactions to explain the multi-stage oxidation.