"Catalysis has the potential to play a significant role in the converting biomass feedstock to commodity chemicals and fuels. There are a few requirements for the catalysts to fulfill during the biorefinery process: optimal reactivity and high selectivity under relatively mild reaction conditions. These properties can be optimized through the choice of catalyst and the morphology of the catalyst support, immobilization chemistry, solvent system for the reaction, and reaction conditions. The purpose of this work is to create and demonstrate a flow-through catalytic reaction system that enhances the target heterogeneous reaction under mild reaction conditions, and to assess the performance of catalyst reactivity and selectivity. To design the flow-through catalytic system, we created a silica-polymer composite inverse opal structure with relatively low defect density to be used as a catalyst support. The construction of the inverse opal structures involved the self-assembly of a template with colloidal polystyrene nanospheres, deposition of the poly(ethylene glycol)-silica sol gel composite precursors in the interstitial spaces between the colloidal spheres, and removal of the template nanospheres by dissolution. The addition of PEG into the silica sol gel modifies the morphology of inverse opal structures to reduce defect density. The resulting inverse opals were characterized by scanning electron microscopy (SEM). By optimizing the composition and molecular weight of polymer, the composite inverse opal structure was improved to reduce the number of defects compared to a silica sol gel inverse opal. The inverse opal structure was replaced by a porous glass frit because of the improved structural integrity of the latter as well as its reduced resistance to flow when used in a flow-through catalytic format. Using Glucose Oxidase (GOx) as a catalyst, a porous glass frit was shown to be a practical, functional catalyst support that compared favorably to the inverse opal support. We chose porous glass frits as catalyst supports for further studies with flow-through catalytic reactions. Using a porous glass frit support, the catalytic performance of palladium nanoparticles was evaluated in a flow-through reaction format. The reactivity and selectivity of the catalyst was assessed by heterogeneous hydrogenation of p-coumaric acid and cinnamaldehyde under mild conditions and in different solvents. A microelectric actuator control system was used to maintain H2(g) level in the reaction stream. The results of this work demonstrate high efficiency and the requisite selectivity for the reactions used. This work represents an initial step in the development of a catalysis system for biomass conversion and biorefinery processing."--Pages ii-iii.
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