Acid–base properties and catalytic activity of nanophase ceria–zirconia catalysts for 4-methylpentan-2-ol dehydration

(Note: The full text of this document is currently only available in the PDF Version )

M G. Cutrufello, I Ferino, V Solinas, A Primavera, A Trovarelli, A Auroux and C Picciau


Abstract

The room-temperature high energy ball-milling technique was used to prepare nanophase Ce1-xZrxO2 (x=0; 0.2; 0.5; 0.8; 1) catalysts. The acid–base properties of these catalysts were investigated by means of adsorption microcalorimetry, using NH3 and CO2 as probe molecules. The catalytic activity for 4-methylpentan-2-ol dehydration was tested at atmospheric pressure in a fixed-bed flow microreactor. The inclusion of increasingly high contents of zirconium into the ceria lattice has a complex influence on the acidity and basicity of the pure parent oxide, in terms of both number and strength of the sites. A maximum in 1-alkene selectivity is observed for the ceria-rich catalyst and a minimum for the zirconia-rich sample. Catalytic results are correlated with the acid–base properties and can be interpreted in the light of the mechanism formerly proposed for zirconia, ceria and lanthania. Surface conditioning of the zirconia-rich catalyst occurs during the run, resulting in a remarkable variation of selectivity.


References

  1. P. Fornasiero, R. Di Monte, G. Ranga Rao, J. Kaspar, S. Meriani, A. Trovarelli and M. Graziani, J. Catal., 1995, 151, 168 CrossRef CAS.
  2. Y. Sun and P. A. Sermon, J. Mater. Chem., 1996, 6, 1025 RSC.
  3. F. Zamar, A. Trovarelli, C. de Leitenburg and G. Dolcetti, Stud. Surf. Sci. Catal., 1996, 101, 1283 CAS.
  4. C. de Leitenburg, A. Trovarelli, F. Zamar, S. Maschio, G. Dolcetti and J. Llorca, J. Chem. Soc., Chem. Commun., 1995, 2181 RSC.
  5. A. Trovarelli, F. Zamar, J. Llorca, C. de Leitenburg, G. Dolcetti and J. T. Kiss, J. Catal., 1997, 169, 490 CrossRef CAS.
  6. G. Balducci, J. Kašpar, P. Fornasiero, M. Graziani, M. S. Islam and J. D. Gale, J. Phys. Chem. B, 1997, 101, 1750 CrossRef CAS.
  7. V. R. Choudary and V. H. Rane, J. Catal., 1991, 130, 411 CrossRef CAS.
  8. K. Tomke, in Proceedings of Sixth International Congress on Catalysis, ed. G. C. Bond, P. B. Wells and F. C. Thomkins, The Chemical Society, London, 1977, vol. 1, p. 105 Search PubMed.
  9. A. Auroux, P. Artizzu, I. Ferino, R. Monaci, E. Rombi, V. Solinas and G. Petrini, J. Chem. Soc., Faraday Trans., 1996, 92, 2619 RSC.
  10. P. Käβner and M. Baerns, Appl. Catal., 1996, 139, 107 CrossRef.
  11. A. Auroux, P. Artizzu, I. Ferino, V. Solinas, G. Leofanti, M. Padovan, G. Messina and R. Mansani, J. Chem. Soc., Faraday Trans., 1995, 91, 3263 RSC.
  12. A. Auroux, P. Artizzu, I. Ferino, R. Monaci, E. Rombi and V. Solinas, Microporous Mater., 1997, 11, 117 CrossRef CAS.
  13. K. Tanabe, T. Sumiyoshi, K. Shibata, T. Kiyoura and J. Kitagawa, Bull. Chem. Soc. Jpn., 1974, 47, 1064 CAS.
  14. H. H. Kung, J. Solid State Chem., 1984, 52, 191 CrossRef CAS.
  15. A. Trovarelli, Catal. Rev.-Sci. Eng., 1996, 38, 439 Search PubMed.
  16. V. Bolis, C. Morterra, M. Volante, L. Orio and B. Fubini, Langmuir, 1990, 6, 695 CrossRef CAS.
Click here to see how this site uses Cookies. View our privacy policy here.