Reaction Pathways of Biomass-Derived Oxygenates over Metals and Carbides: From Model Surfaces to Supported Catalysts

The conversion of lignocellulosic biomass-derived oxygenates into renewable fuels and chemicals requires the control of bond-scission sequences. For example, selective CO/CO bond scission is needed to reduce the oxygen content and thus increase the energy density to produce renewable fuels. On the other hand, the control of CC bond scission is desired for producing H-2 and suppressing side products from CO/CO bond-scission reactions. In this review, recent advances in the utilization of bimetallic and metal carbide catalysts that demonstrate enhanced performance and/or low cost for the selective CC and CO/CO bond-scission reactions, are summarized. Furthermore, the importance of combining density function theory (DFT) calculations, microkinetic modeling, and ultrahigh vacuum (UHV) experiments on single-crystal model surfaces with reactor evaluations over the corresponding powder catalysts is illustrated. General trends and future opportunities for the control of bond-scission sequences of biomass-derived oxygenates are also discussed.