Characterization of supported cobalt catalysts for CO hydrogenation /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1988.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | Temperature-programmed reduction, X-ray photoelectron spectroscopy, and X-ray diffraction have been used as characterization techniques to investigate the effects caused by the support and metal precursor on the catalytic and reduction behaviors of dispersed cobalt CO hydrogenation catalysts. Silica, cerium oxide, and lanthanum oxide have been employed as supports. The nitrate, chloride, and acetate salts were used as the cobalt precursors. Both calcined and uncalcined catalysts have been studied. Under almost all of the conditions studied, the cobalt nitrate-derived catalysts had the highest activity for CO hydrogenation. The cobalt chloride-derived catalysts were generally poor catalysts with very low activity, unless the catalysts were calcined prior to the reduction process. The support appears to be the dominant factor in reaction selectivity with the average chain length of the hydrocarbon products having the following order: Co/La2O3 > Co/CeO2 > Co/SiO2. The cobalt precursor did not have any measureable effect on the reaction selectivity, but it had a strong influence on overall catalyst activity. It has been shown that both the support and the precursor affect the calcination process. Complete conversion of the precursor to Co3O4 occurs only for the CeO2-supported catalysts. Co3O4 was not detected for cobalt acetate supported on silica. The La2O3-supported catalysts formed LaCoO3 as a result of the calcination process. These species had different reduction behaviors from the uncalcined catalysts as shown by changes in CO hydrogenation activity, temperature-programmed reduction profiles, and X-ray photoelectron spectra. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Chemistry." |
| Physical Description: | xvii, 198 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |