Catalytic Lignin Valorization
By some estimates, catalysts are required in 85% of all petrochemical refining processes. We expect biorefining processes to be similarly reliant on catalysis to generate new materials. Our group is interested in engineering reactions and processes that extract and upgrade lignin using economically and environmentally sustainable methods to afford new monomers for advanced materials.
We focus our attention on catalytic transfer hydrogenation and hydrogenolysis, which affords reducing conditions without petroleum-derived hydrogen gas. Instead, we use biomass-derived ethanol as our reaction solvent and reducing agent. This allows us to control the oxidation state of aliphatic and aromatic carbons in lignin, which we believe is important for physical properties of new materials we make from it.
We are also interested in exploring new catalytic materials derived from earth-abundant elements. We have focused primarily on first-row transition metals (such as Iron, Cobalt, and Nickel) because they are far less scarce (and therefore environmentally friendly) than noble metals. We synthesize and characterize these using state-of-the-art techniques.
We synthesize intermetallic complexes of first-row transition metals and Group 13 elements (B, Al, and Ga), because we believe these species will afford novel electronic features and a resistance to coking. Taken together, these are both extremely important to biomass valorization efforts, where a catalyst must be able to mediate certain transformations among several hundred possibilities while maintaining a long lifetime to maximize yields of high-value products.