Topics in Catalysis

, Volume 55, Issue 1–2, pp 84–92 | Cite as

Chemisorption and Dehydration of Ethanol on Silica: Effect of Temperature on Selectivity

Original Paper

Abstract

Dissociative chemisorption of ethanol on partially dehydroxylated silica is investigated by (i) exposing silica to gas-phase ethanol at various temperatures (ranging between 373 and 773 K) and (ii) analyzing the material using temperature-programmed desorption and in situ infrared spectroscopy. This chemisorption leads to formation of isolated surface ethoxide species via dehydration of ethanol at reaction temperatures above 573 K, and, at lower temperatures, it favors the synthesis of silanol–ethoxide functionality via a pathway involving opening of siloxane Si–O–Si bridges. The activation barrier for ethene desorption from the isolated surface ethoxide species is considerably higher relative to that for ethanol desorption from the hydrogen-bound silanol–ethoxide pairs. These single-turnover experiments allow predicting the product distribution of ethanol chemisorption on silica depending on the treatment conditions, e.g. temperature of interaction between ethanol and silica, and suggest why, in general, dehydration catalysis on silica requires high temperatures, in order to avoid non-productive chemisorption via opening of siloxane bridges.

Keywords

Chemisorption Silica Ethanol Ethene TPD Dehydration Infrared spectroscopy 

Supplementary material

11244_2012_9771_MOESM1_ESM.doc (404 kb)
Supplementary material 1 (DOC 404 kb)

References

  1. 1.
    Natal-Santiago MA, Dumesic JA (1998) J Catal 175:252CrossRefGoogle Scholar
  2. 2.
    Mertens G, Fripiat JJ (1973) J Colloid Interface Sci 42:169CrossRefGoogle Scholar
  3. 3.
    Borello E, Zecchina A, Morterra C, Ghiotti G (1967) J Phys Chem 71:2945CrossRefGoogle Scholar
  4. 4.
    Kondo S, Fujiwara H, Okazaki E, Ichii T (1980) J Colloid Interface Sci 74:328CrossRefGoogle Scholar
  5. 5.
    Jeziorowski H, Knoezinger H, Meye W, Muller HD (1973) J Chem Soc Faraday Trans I 69:1744CrossRefGoogle Scholar
  6. 6.
    Borello E, Zecchina A, Morterra C (1967) J Phys Chem 71:2938CrossRefGoogle Scholar
  7. 7.
    Kubelkova L, Schurer P, Jiru P (1969) Surf Sci 18:245CrossRefGoogle Scholar
  8. 8.
    Tedder LL, Lu GQ, Crowell JE (1991) J Appl Phys 69:7037CrossRefGoogle Scholar
  9. 9.
    Danner JB, Vohs JM (1993) Appl Surf Sci 72:409CrossRefGoogle Scholar
  10. 10.
    Kwak JH, Mei D, Peden CHF, Rousseau R, Szanyi J (2011) Catal Lett 141:649CrossRefGoogle Scholar
  11. 11.
    Kim KS, Barteau MA, Farneth WE (1988) Langmuir 4:533CrossRefGoogle Scholar
  12. 12.
    Tanabe K, Misono M, Ono Y, Hattori H (1989) New solid acids and bases: their catalytic properties, vol 51, Elsevier, AmsterdamGoogle Scholar
  13. 13.
    Lusvardi VS, Barteau MA, Farneth WE (1995) J Catal 153:41CrossRefGoogle Scholar
  14. 14.
    Chiang H, Bhan A (2010) J Catal 271:251CrossRefGoogle Scholar
  15. 15.
    Mirth G, Eder F, Lercher JA (1994) Appl Spectrosc 48:194CrossRefGoogle Scholar
  16. 16.
    Zhuravlev LT (2000) Colloids Surf A 173:1CrossRefGoogle Scholar
  17. 17.
    Redhead PA (1962) Vacuum 12:203CrossRefGoogle Scholar
  18. 18.
    Jin T, Jo SK, Yoon C, White JM (1989) Chem Mater 1:308CrossRefGoogle Scholar
  19. 19.
    Idriss H, Barteau MA (2000) Adv Catal 45:261CrossRefGoogle Scholar
  20. 20.
    Fleischman SD, Scott SL (2011) J Am Chem Soc 133:4847–4855CrossRefGoogle Scholar
  21. 21.
    Minibaev RF, Zhuravlev NA, Bagatur’yantz AA, Alfimov MV (2009) Russ Phys J 52:1164CrossRefGoogle Scholar
  22. 22.
    Luts T, Iglesia E, Katz A (2011) J Mater Chem 21:982CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Department of Chemical and Biomolecular EngineeringUniversity of California at BerkeleyBerkeleyUSA

Personalised recommendations