AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Reduction of Fe(III) by Soot
Hector Casique, Ashleen Reddy, Casey Neumann, ANNE JOHANSEN, Central Washington University
Abstract Number: 458 Working Group: Carbonaceous Aerosols in the Atmosphere
Abstract Combustion of fuels leads to the emission of carbonaceous soot particles that also contain organic molecules and trace metals. Despite indications that quinone-like structures and ferrous iron contribute to soot toxicity, not much is known about how these compounds are produced during combustion and after emission into the atmosphere. The purpose of this research is to study model iron-soot systems under conditions encountered in the tail pipe and in the atmosphere in order to increase our understanding of the iron redox processes that control iron speciation and surface functional groups of the soot. Wet-chemical as well as spectroscopic techniques are used to determine changes in iron speciation and soot characteristics in a variety of settings. Results show that under reducing atmospheric environments as well as in sunlight, iron is effectively reduced in the presence of soot. These results indicate that the toxicity of soot may depend on tailpipe conditions as well as ageing of aerosol particles before inhalation.