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dc.contributor.advisorMcDeavitt, Sean M.en_US
dc.creatorWegener, Jeffrey J.en_US
dc.date.accessioned2010-01-14T23:54:04Zen_US
dc.date.accessioned2010-01-16T00:03:20Z
dc.date.available2010-01-14T23:54:04Zen_US
dc.date.available2010-01-16T00:03:20Z
dc.date.created2008-12en_US
dc.date.issued2010-01-14en_US
dc.identifier.urihttp://hdl.handle.net/1969.1/ETD-TAMU-2008-12-83
dc.description.abstractThe experiments performed for this research were completed to produce solid cerium oxide microspheres by an internal gelation sol-gel process. The motivation for this work was to develop a process that would enable the fabrication of a storage or transmutation form for the plutonium and transuranics (TRU) from the Uranium Extraction Plus (UREX ) used fuel reprocessing process. This process is being investigated by the Department of Energy (DOE) and the Advanced Fuel Cycles Initiative (AFCI) through the Nuclear Energy Research Initiative. The internal gelation production of cerium oxide involves the combination of hexamethylenetetramine (HMTA), urea, and cerium nitrate solutions at ~100oC. Microspheres were produced by injection of a broth solution into a flowing stream of hot silicone oil. The captured microspheres were aged, washed, and then underwent Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and XRay Diffraction (XRD) analysis. The process variables examined in this study include the concentrations of HMTA, urea and cerium nitrate, the process temperature, the postgelation aging time, and the product washing conditions. Over a series of 70 experiments, it was determined that a broth solution containing a mixture of 1.45 M cerium nitrate and 1.65 M HMTA and urea (1:1 ratio) solutions produced the best cerium oxide microspheres. The spheres were aged for 30 to 60 minutes and then washed in hexane to remove the silicone oil and a subsequent series of ammonium hydroxide washes to remove unreacted product and to fully gel the microspheres. Through DSC analysis it was determined that excess wash or unreacted product may be removed by an exothermic reaction at approximately 200oC. The XRD analysis of unheated spheres showed the presence of cerium oxide with additional cerium-bearing organics. Following heating, the microspheres were completely converted to cerium oxide.en_US
dc.format.mimetypeapplication/pdfen_US
dc.language.isoen_USen_US
dc.subjectInternal Gelation Sol-Gelen_US
dc.subjectMicrospheresen_US
dc.subjectCerium Oxideen_US
dc.titleProduction of cerium oxide microsheres by an internal gelation sol-gel processen_US
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentNuclear Engineeringen_US
thesis.degree.disciplineNuclear Engineeringen_US
thesis.degree.grantorTexas A&M Universityen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelMastersen_US
dc.contributor.committeeMemberPoston, John W.en_US
dc.contributor.committeeMemberRadovic, Miladinen_US
dc.type.genreElectronic Thesisen_US


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