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Gas Phase Oxidation Of Levulinic Acid For The Production Of Maleic Anhydride Over Supported Vanadium Oxide Catalysts, Anargyros Chatzidimitriou
Gas Phase Oxidation Of Levulinic Acid For The Production Of Maleic Anhydride Over Supported Vanadium Oxide Catalysts, Anargyros Chatzidimitriou
Dissertations - ALL
With continued depletion of fossil carbon, there is a need to utilize renewable sources of energy and consumer end products. In this context, we examine the aerobic oxidation of levulinic acid, a bio-based platform chemical derived from lignocellulosic biomass, to produce maleic anhydride, a valuable commodity chemical. This process is carried out over supported vanadium oxide catalysts. Yields as high as 71% of the theoretical maximum were achieved at 573 K over a vanadium oxide catalyst supported on SiO2. The exact mechanism underlying this transformation is complex, but our results suggest that maleic anhydride forms by the oxidative cleavage of …
Characterization Of Polyacrylonitrile Carbon Fibers, Christian Burke Iversen
Characterization Of Polyacrylonitrile Carbon Fibers, Christian Burke Iversen
Biomedical and Chemical Engineering – Theses
Carbon fiber composites are a widely used, advanced material with exceedingly high strength to weight properties. In this thesis, a literature overview of carbon fiber manufacturing was provided, as well as a thorough analysis of in- house electrospun polyacrylonitrile fiber stabilization and surface modification of the resulting carbon fibers. In the first section, an overview of precursor fiber fabrication is provided, followed by an analysis of stabilization using surface and bulk composition, dimensional analysis, and functional group analysis via FTIR. The second section uses the current stabilization procedure to develop carbon nanofibers. Fibers first underwent a nitric acid oxidation time …