Importance of O(3P) atoms and OH radicals in hydrocarbon oxidation during the nonthermal plasma treatment of diesel exhaust inferred using relative-rate methods

The consumption of acetylene and propene during passage of simulated diesel exhaust through a nonthermal plasma at 453 K and atmospheric pressure was studied using experimental and computational techniques. Experimental observations of the relative decay rates of acetylene and propene and computer modeling of the chemical and physical processes in the plasma suggest that O(P-3) atoms and, to a lesser extent, OH radicals are the dominant species responsible for initiating hydrocarbon oxidation in this system. Results are discussed in terms of the gas-phase chemistry occurring during the nonthermal Plasma treatment of diesel exhaust. (C) 2003 Wiley Periodicals, Inc.