Kinetics and Mechanisms of Lignin Model Compound Reactions over a Hydrotalcite-Derived Copper Catalyst

The reactivity of molecular compounds relevant to the hydrogenolysis of lignin as a renewable source of aromatics was explored in a combined experimental-computational approach. X-ray absorption spectroscopy shows that highly dispersed copper ions are reduced by the solvent, methanol, in the early stages of the reaction. The resulting copper nanoparticles catalyze methanol reforming to generate H2 at ca. 250 °C. The selectivity towards the desired C-O hydrogenolysis reaction was explored for a variety of model compounds, including anisole and dihydrobenzofuran. DFT calculations suggest that the barrier is lowest for C-O cleavage, but the oxide support may play a role in directing substrate adsorption and therefore reactivity. This was confirmed experimentally by observing reaction products in a flow reactor.