Reactions of C3- and C4-hydrocarbons

From simulations of a number of laminar premixed flames of C3- and C4-hydrocarbons, it is known (Warnatz, 1981) that after the initial H-atom abstraction by H, O, or OH, the destiny of the alkyl radicals formed is the central point of interest. Due to the instability of C3- and C4-alkyl radicals with respect to thermal decomposition (see below), the competing reactions with O or O2 and recombination or disproportionation reactions are unimportant in flame propagation. 

Finally, the decomposition reactions of C3H4 and C4H2 are discussed in this section because of the importance of these species in rich hydrocarbon flames (Warnatz et al, 1982). 

As in the combustion of CH4 and C2H5, the abstraction reactions of H, OH, and (to a lesser extent) O with the hydrocarbon fuel provide the main fuel consumption in flame propagation, whereas the reaction with HO2 is unimportant due to the low HO2 concentration and the small rate coefficients. In contrast to CH4 and C2H5 combustion, for higher hydrocarbons not only the global rate coefficients for the attack of H, O, and OH are of interest but 

Hiatt and Benson (1972) Golden et al. (1973) Golden et al. (1974b) Parkes and Quinn (1975) Parkes and Quinn (1976) 

Kerr and Parsonage (1972) Wagner and Zellner (1972c) Yano (1977) 

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