Download or read book Preferential Oxidation of Carbon Monoxide Over Heat Treated Swellable Organically Modified Silica Supported Cobalt Oxide Catalyst written by Dishari Basu and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The increasing global spotlight on environmentally friendly processes has driven the recent progress in proton exchange membrane fuel cell (PEMFC) technology. PEMFCs require an ultra-pure hydrogen stream as the feed gas. As little as 10 ppm of carbon monoxide (CO) in this feed can poison the platinum-based catalyst which is used in the anode of PEMFCs. Thus, this hydrogen feed stream must be purified by preferential oxidation (PROX) of CO prior to its introduction to a PEMFC. Supported precious metal catalysts have been extensively studied for catalyzing the CO PROX reaction. However, due to their lack of abundance and high costs, relatively inexpensive transition metal oxide based catalysts are promising alternatives. In this category, cobalt based catalysts have shown the most favorable results for catalyzing CO PROX. However, moisture present in the hydrogen feed has been found to considerably decrease PROX performance with time over Co based catalysts. Therefore, the synthesis of an inexpensive, water resistant Co based catalyst is required. Moisture causes decrease in PROX activity by plugging the Co3+ active sites and forming inactive complexes. To protect these active sites from H2O, a novel hydrophobic material, known as swellable organically-modified silica (SOMS) was used as the support material. However, the small pore diameter of SOMS did not allow the reactants to contact the active sites situated within its matrix. Therefore, SOMS was heat treated to tune its properties such as pore size and degree of hydrophobicity for application to this reaction. This heat treated SOMS (HSOMS) was then used to support the active Co3O4 nanoparticles. Dry and wet feed reactions were performed in a fixed bed reactor to obtain activity parameters such as CO conversion and selectivity. The effect of promotion and varying synthesis techniques was studied to synthesize a catalyst with high activity in the dry feed. The performance of the most water tolerant catalyst among the various HSOMS supported catalysts was compared to that of silica supported Co3O4. Detailed textural and surface characterization tests such as N2 physisorption, XRD, XPS and TPR were performed to understand the support morphology, phase identification of cobalt oxide, oxidation state of cobalt on the surface and reducibility of the catalyst respectively. Modifying the conventional synthesis procedure and tuning the properties of SOMS resulted in the synthesis of a more water resistant, active and stable supported Co3O4 catalyst.