2018 Spring Symposium
Robert J. Davis, Department of Chemical Engineering, University of Virginia, Charlottesville, VA, USA
Abstract – Selective oxidation of alcohols to carbonyl compounds is an important reaction in organic synthesis and will likely play a significant role in the development of value-added chemicals from biomass. The industrial application of a precious metal catalyst such as Pt, however, can be hindered by deactivation and high price. We have therefore explored the mode of deactivation during alcohol oxidation on Pt by in-situ spectroscopy and studied the role of various promoters on catalyst performance. Results confirm that slow decarbonylation of product aldehyde deposited unsaturated hydrocarbon on the surface that blocked access to the active sites. Addition of Bi as a promoter did not prevent the decarbonylation side reaction, but instead enhanced the activation of dioxygen during the catalytic cycle. In an effort to avoid the use of precious metals altogether, the oxidation of alcohols over atomically-dispersed, non-precious metal cations (Fe, Cu, and Co) located in a nitrogen-doped carbon matrix was demonstrated. Extensive characterization of these non-precious metal catalysts revealed important insights into the oxidation mechanism and stability of this new class of atomically-dispersed metal catalyst.