(670d) Evaluation of Metal Oxides for Partial Deoxygenation of Pyrolysis Vapors From Northeast US Biomass

The presences of reactive oxygenated compounds in pyrolysis oil make it inferior to petroleum feedstocks and unsuitable for use as transportation fuel or heating oil. Deoxygenation of the pyrolysis vapors with heterogeneous catalysts is one of the approaches utilized in transforming pyrolysis oil/vapor into hydrocarbon fuel.  In this study, partial deoxygenation of primary pyrolysis vapors over various metal oxides was investigated as a stabilization approach in removing destabilizers such as aldehydes and carboxylic acids. A bench scale pyrolysis system (Py-GC/MS) was used to investigate catalytic pyrolysis of cellulose, xylan, lignin, sugar maple, willow and switchgrass at 550 ^oC.  Three forms of TiO₂ (nanorods, anatase, and rutile) were investigated as well as the effect of loading the catalysts with 1wt% and 5wt% of Ni and Pt. Other types of metal oxides that were studied include CeO₂, ZrO₂, and MgO. The catalysts were characterized using TEM, XRD, and NEXAFS. In this presentation, the reactivity of the various catalysts on hydroxycarbonyls with 2-4 carbon atoms, diketones, carboxylic acids and anhydrosugars will be discussed. The product distribution showed that titania and ceria were more selective towards the formation of linear and cyclic ketones.