Guaiacol Hydrodeoxygenation over Platinum Catalyst: Reaction Pathways and Kinetics

Guaiacol represents a large fraction of lignin derived pyrolysis bio-oils. It was shown in our prior work that Pt has higher activity and stability for guaiacol hydrodeoxygenation as compared to other noble metal catalysts. In the present study, further theoretical and experimental investigations were conducted to reveal the reaction pathways and kinetics. For Pt/C catalyst in a fixed-bed reactor, the main liquid phase reaction products were phenol, catechol and cyclopentanone. Because cyclopentanone was typically not observed in the prior literature, a pathway for its formation was proposed and supported by density functional theory (DFT) calculations. By varying the space velocity, kinetic data was acquired in the temperature range 275 to 325 degrees C. The rate constants and activation energies for each subreaction in the network were obtained based on the power-law model.