This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
0853682 and 0853950 Pignatello and Mao
Sorption by the soil/sediment organic matter (SOM) fraction of geosolids controls the fate of nonionic organic compounds in the environment, and is an underlying process affecting decision-making in analytical chemistry, risk assessment, and remediation strategy for specific pollutants. While NMR spectroscopy is potentially a powerful molecular-scale tool, it has so far provided limited insight into the mechanisms of sorption by solid-state SOM due to poor resolution. In the last few years, however, significant advances many by one of the PIs have been made in acquisition and spectral editing techniques of solid state NMR (1H, 13C, 129Xe and 2D analysis) that have yielded valuable new information about the structure of SOM solids. The PIs will apply many of these techniques, in combination with sorption experiments, to gain information about the nature of the sorbed complex. Materials of focus will include humic acid particles, whole soils and isolated SOM, black carbon standards, coal reference standards, and polymer standards. The objectives are: a) to probe structural changes of SOM taking place during sorption; b) to probe preferential sites of sorption in SOM in regions chemically homogeneous on a scale large enough to serve as separate sorption domains; and c) to quantify fused ring content and size and their influence on sorption affinity.
The results of this work will influence the way research is designed and the way major concepts are taught in environmental engineering and science. Society will benefit broadly by changes in approaches to risk assessment and remediation design that will result from an improved conceptual model of the sorption process. The collaboration will significantly build research infrastructure because it will open additional avenues that can be explored in environmental engineering and science with NMR. The involvement of Native Americans through connections to tribal colleges is a strong feature of the educational benefits that can be derived from this work. Post-docs from the Pignatello research group have secured faculty positions at institutions where they will likely increase participation of under-represented populations to STEM disciplines. The curriculum materials to be developed for on-line resources for science teachers would allow effective dissemination of results to the K-12 level.