(114f) Vapor Phase Catalytic Deoxygenation of Acetic Acid

When biomass is converted to a liquid bio-oil through pyrolysis, it has a significantly higher oxygen content compared to petroleum fractions. In order to convert the pyrolysis products into infrastructure-compatible fuels, oxygen removal is required. Oxygen removal can be achieved by both hydrotreating (which requires the addition of hydrogen) and decarboxylation or decarbonylation, whereby oxygen is rejected as CO₂ and CO, respectively.  Solid acid zeolite catalysts have been studied for bio-oil deoxygenation, but suffer from rapid deactivation due to coke formation which renders the pores and active sites inaccessible to reactants.  In order to minimize wasted carbon and efficiently utilize biomass to create hydrocarbon fuels, selective deoxygenation is critical. In order to develop catalysts with an improved selectivity towards deoxygenation rather than coking, as compared to standard solid acid catalysts.

In the present contribution, Pt and Pd catalysts were tested for their activity and selectivity in deoxygenation of model biomass-derived oxygenated compounds (e.g., acetic acid, phenol).  Pd catalysts on various supports have been studied, as well as various particles sizes, and Pd has been shown to be active for decarboxylation of long chain carboxylic acids. Comparison of catalytic activity of materials for different compounds, as well as material characterization results will be discussed.