Identifying molecular changes in the chromophoric dissolved organic matter of oxidized waste streams

AGRO 182

William T. Cooper, and Dan Osborne, Department of Chemistry and Biochemistry, Florida State University, Dittmer Bldg, 95 Chieftan Way, Tallahassee, FL 32306
Landfill leachates are complex, heterogeneous mixtures that containing levels of dissolved organic matter (DOM) that far exceed those in domestic wastewaters. On-site advanced oxidation followed by dispersed surface application has been suggested as a treatment option, but little is known about the oxidation potential of the high molecular weight chromorphoric component (CDOM) of leachate. We have used a combination of 3-dimensional excitation-emission matrix fluorescence spectroscopy (EEMS) and ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to characterize the changes in leachate DOM after oxidation by UV irradiation and ozonation. EEMS measurements indicate that about 93% of the fluorescent components of leachates can be removed after 2 hr of ozone or ozone/UV oxidation. High-field (9.4 Tesla) FT-ICR MS was able to resolve fully the individual compounds in the treated leachate DOM and to identify the fluorescesing components that were removed.

Environmental Forensics
8:50 AM-11:40 AM, Wednesday, August 20, 2008 Crowne Plaza City Center -- Independence A/B, Oral

Division of Agrochemicals

The 236th ACS National Meeting, Philadelphia, PA, August 17-21, 2008