Experimental profiles of stable species concentrations and temperature are reported for the flow reactor oxidation of ethanol at atmospheric pressure, initial temperatures near 1100 K and equivalence ratios of 0.61-1.24. Acetaldehyde, ethene, and methane appear in roughly equal concentrations as major intermediate species under these conditions. A detailed chemical mechanism is validated by comparison with the experimental species profiles. The importance of including all three isomeric forms of the C2H50 radical in such a mechanism is demonstrated. The primary source of ethene in ethanol oxidation is verified to be the decomposition of the C2H4OH radical. The agreement between the model and experiment at 1100 K is optimized when the branching ratio of the reactions of CzH50H with OH and H is defined by (30% C2H40H + 50% CHsCHOH + 20% CH3CH20) + XH. As in methanol oxidation, HOn chemistry is very important, while the H + 0 2 chain branching reaction plays only a minor role until late in fuel decay, even at temperatures above 1100 K.

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A single kinetic mechanism for methanol pyrolysis is tested against multiple sets of experimental data for the first time. Data are considered from static, flow, and shock tube reactors, covering temperatures of 973 to 2000 K and pressures of 0.3 to 1 atmosphere. The model results are highly sensitive to the rates of unimolecular fuel decomposition and of various chain termination reactions that remove CHzOH and H radicals, as well as to experimental temperature uncertainties. The secondary fuel decomposition reaction CH,OH = CH,OH + H. which has previously been included only in mechanisms for high temperature conditions, is found to have a significant effect a t low temperatures as well, through radical recombination. %'he reaction CH,O 4 C = CH3 + C 0 2 , rather than CHIOH + H = CH,? t H20, is found to be the dominant source of CH3 a t low temperatures. The reverse of CH, + OH = CH,OH T H is important to CHs production at high temperatures.

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