Details zur Publikation |
| Kategorie | Textpublikation |
| Referenztyp | Zeitschriften |
| DOI | 10.1016/j.jcat.2004.11.045 |
| Titel (primär) | Interaction between sulfated zirconia and alkanes: prerequisites for active sites - formation and stability of reaction intermediates |
| Autor | Li, X.B.; Nagaoka, K.; Simon, L.J.; Lercher, J.A.; Wrabetz, S.; Jentoft, F.C.; Breitkopf, C.; Matysik, S.; Papp, H. |
| Quelle | Journal of Catalysis |
| Erscheinungsjahr | 2005 |
| Department | EXPOEPID |
| Band/Volume | 230 |
| Heft | 1 |
| Seite von | 214 |
| Seite bis | 225 |
| Sprache | englisch |
| Keywords | Sulfated zirconia; Alkanes; Isomerization; Active sites; Reaction intermediates; Transient measurements |
| Abstract | Two sulfated zirconia catalysts were prepared via sulfation and calcination of zirconium hydroxide at 873 K; the zirconium hydroxide had been aged at room temperature for 1 h (SZ-1) or aged at 373 K for 24 h (SZ-2). SZ-1 was active for n-butane isomerization at 373 K; SZ-2 reached a similar performance level only at 473 K. Both materials contained about 9 wt% sulfate and were tetragonal. Because of a lower BET surface area (105 vs. 148 m2/g) SZ-1 featured a higher sulfate density, and XRD and EXAFS analysis showed larger (ca. 10 nm) and more well ordered crystals than for SZ-2. n-Butane TPD on SZ-1 showed a butene desorption peak at low temperature, whereas no obvious butene desorption was observed with SZ-2, suggesting that SZ-1 has a higher oxidizing power at low temperature than SZ-2. The number of sites capable of dehydrogenation are less than 5 μmol/g, because the differential heats of n-butane adsorption as measured by microcalorimetry were 45–60 kJ/mol for higher coverages, indicating weak and reversible interaction. TAP experiments describe the adsorption and desorption behavior of n-butane at different activity states and are the basis for a simple adsorption model. Reactant pulses and purge experiments show that the active species, presumably formed in an oxidative dehydrogenation step, are stable at the surface under reaction conditions. |
| dauerhafte UFZ-Verlinkung | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=3570 |
| Li, X.B., Nagaoka, K., Simon, L.J., Lercher, J.A., Wrabetz, S., Jentoft, F.C., Breitkopf, C., Matysik, S., Papp, H. (2005): Interaction between sulfated zirconia and alkanes: prerequisites for active sites - formation and stability of reaction intermediates J. Catal. 230 (1), 214 - 225 10.1016/j.jcat.2004.11.045 |
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