Elementary Processes in Combustion and Sooting of Coal-Derived Fuels. Progress Report: 2nd Year, 3rd Quarter, February 10-May 9, 1984

摘要

Combustion of aromatics - Our work on understanding the basic chemical processes in the combustion and sooting of aromatic-rich synfuels continues as we explore the reactivity of the benzenes. Of particular concern is the degradation on the aromatic ring and the formation of the smaller molecular, ionic and radical fragments. One central problem is that the elementary reaction products are themselves reactive and difficult to observe. We continue to adapt the technique of free jet expansions to facilitate the direct observation and characterization of combustion intermediates. Efforts have continued to isolate the nascent products of the attack of simple radicals on the aromatic ring. In particular, the reaction of methylene, CH sub 2 , with benzene serves as a prototype. The final product is toluene and the suspected intermediates are cycloheptatriene and norcaradiene. Both intermediates have been separately characterized in our laboratory. The following observations have been made on the reactivity of ions derived from aromatics: the C sub 6 H sub 5+ aromatic cation is relatively stable with respect to decomposition in our reactor system; subsequent chemistry can be initiated by photo-excitation and formation of C sub 4 H sub 3+ ; reactions produced small fragments, including C sub 1 and C sub 2 species. (ERA citation 10:019856)