NSF Award
1939948
Lignin is a polymeric material from plants that is currently burned for energy in biorefinery processes. The goal of this project is to convert lignin to other potentially more valuable products in an electrochemical reactor. This would yield potentially higher-value uses for lignin, which could improve biorefinery economics and eventually reduce the cost to produce next-generation biofuels. In addition, products generated from lignin could replace chemicals currently sourced from petroleum. Reduced dependence on petroleum could address the United States' energy and materials security. Currently, the mechanism governing conversion of lignin is not well-understood. This project seeks to address that fundamental issue by investigating the conversion of less complex model compounds that share some features with lignin. Generating better understanding of how these reactions occur would advance the field of biomass conversion and could eventually lead to a more environmentally friendly way to generate biofuels and bioproducts. This project also contains an educational outreach program focused on high school students in Appalachia who are underrepresented in the STEM fields. The outreach program seeks to increase Appalachian students' matriculation in the STEM fields at four-year colleges and universities, which would diversify STEM workers' backgrounds.<br/><br/>The goal of this project is to develop better understanding of the reaction pathways that dominate electrochemical conversion of lignin. Because of the complexity of the lignin biopolymer, the PIs will work with lignin model compounds that share key features with lignin itself. The project will involve the electrochemical oxidizidation of the lignin model compounds at different electrode potentials, and the use of NMR spectroscopy to determine structural changes resulting from electrochemical oxidation. This analysis will be used to elucidate the reaction mechanism. The PIs hypothesize that two major reactions pathways are likely possible: direct electrochemical conversion or indirect conversion mediated by hydroxyl radicals. Additional of hydroxyl radical scavengers will help determine the relative importance of the hydroxyl radical mediated reaction. Once the reaction pathway models have been developed using the lignin model compounds, the PIs will compare and assess the model?s descriptions on lignin itself, determining how well the reaction pathways describe the actual reaction mechanism.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
