Quantitative Characterization of PAHs in Burn Residue and Soot Samples and Differentiation of Pyrogenic PAHs from Petrogenic PAHs−The 1994 Mobile Burn Study

Abstract

Several mesoscale burns were conducted in 1994 in Mobile Bay, AL, to study various aspects of diesel fuel burning in situ. The target PAHs in the diesel, residue, and soot samples collected during each burn were quantitatively characterized by GC/MS. A simple model based on mass balance of individual petroleum PAHs pre- and postburn was proposed to estimate the destruction efficiencies of the total petroleum PAHs. This study demonstrates the following: (1) Distributions of PAHs in the original diesel and soot were very different. (2) The average destruction efficiencies for the total target diesel PAHs including five alkylated PAH series and other EPA priority unsubstituted PAHs were greater than 99%. (3) Using the model, 27.3 kg of the diesel PAHs were destroyed for each 1000 kg of diesel burned. These were mostly two- and three-ring PAHs and their alkylated homologues. (4) Combustion also generated trace amounts of high molecular weight five- and six-ring PAHs as well as the four-ring benz[a]anthracene...