Correlation of PAH structure and fullerenes formation in premixed flames

Combustion products from fuel-rich, premixed flames generated by the burnin g of aliphatic and aromatic fuels were characterized by GC/MS and HPLC with diode-array detection (HPLC/DAD). Fullerenes were efficiently produced in benzene (aromatic) flames, but not in ethylene (aliphatic) flames. The PAH product suites from both types of flames appeared qualitatively similar, wh ether or not the flames were fullerenes-forming. However, oxygen-containing PAH were notably more abundant in fullerenes-forming benzene flames. Ethyl ene flame products were found to be characterized by an abundance of periph erally-fused, relative to internally-fused, cyclopenta-PAH, while the oppos ite was found for the benzene flames. Interestingly, corannulene, a fullere ne subunit, is a product of both aliphatic and aromatic flames. These diffe rences in the product suites may help to elucidate the mechanism of fullere nes formation in the aromatic flames.