Catalysis Letters

, Volume 89, Issue 1–2, pp 55–62 | Cite as

Epoxidation of Styrene by Anhydrous H2O2 over TS-1 and γ-Al2O3 Catalysts: Effect of Reaction Water, Poisoning of Acid Sites and Presence of Base in the Reaction Mixture

  • V.R. ChoudharyEmail author
  • N.S. Patil
  • S.K. Bhargava


The styrene conversion and product (viz. styrene oxide, phenyl acetaldehyde, benzaldehyde) selectivity in the liquid-phase epoxidation of styrene by H2O2 (H2O2/styrene = 2) over TS-1 (Si/Ti = 80) and γ-Al2O3 are strongly influenced by the presence of water and/or base (viz. urea and pyridine) in the reaction mixture. The TS-1 showed high styrene conversion activity but no epoxide selectivity in the absence of any base. When anhydrous H2O2 (24% H2O2 in ethyl acetate), with the continuous removal of the reaction water (using the DeanStark trap), was used instead of 50% aqueous H2O2, both the conversion and epoxide yield are increased drastically for the γ-Al2O3, whereas for the TS-1, the increase in the conversion was quite small and there was also no improvement in the epoxide selectivity and/or yield. However, when urea or pyridine was added in the reaction mixture, the epoxide selectivity for both the catalysts was increased depending on the concentration of the base added; the increase in the selectivity was very large for the TS-1 but small for the γ-Al2O3. Poisoning of the acid sites of the γ-Al2O3 by the chemisorbed ammonia or pyridine (at 100 °C) caused a small decrease in the conversion, but it also caused a large decrease in the epoxide selectivity. However, the pyridine poisoning of the TS-1 caused a little beneficial effect, a small increase in the epoxide selectivity. The ammonia poisoning of the TS-1, however, resulted in a small decrease in the conversion with no improvement in the epoxide selectivity. As compared to the TS-1, the γ-Al2O3 catalyst showed a much better performance in the epoxidation by anhydrous H2O2 with the continuous removal of the reaction water. However, the reaction water, if not removed continuously, is detrimental to the γ-Al2O3, causing a large decrease in the catalytic activity and selectivity for styrene oxide but an increase in the selectivity for benzaldehyde.

epoxidation of styrene anhydrous hydrogen peroxide TS-1 catalyst γ-Al2O3 catalyst catalyst poisoning of acid sites 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    V. R. Grieken, J. L. Sotelo, C. Martos, J. L. G. Fierro, M. López-Granados and R. Mariscal, Catal. Today 61 (2000) 49.Google Scholar
  2. [2]
    Q. Yang, S. Wang, J. Lu, G. Xiong, Z. Feng, X. Xin and C. Li, Appl. Catal. 194–195 (2000) 507–514.Google Scholar
  3. [3]
    Q. Yang, C. Li, J. L. Wang, P. Ying, Q. Xin and W. Shi, Stud. Surf. Sci. Catal. 130 (2000) 221.Google Scholar
  4. [4]
    S. B. Kumar, S. P. Mirajkar, G. C. G. Pais, P. Kumar and R. Kumar, J. Catal. 156 (1995) 163–166.Google Scholar
  5. [5]
    S. C. Laha and R. Kumar, J. Catal. 204 (2001) 64.Google Scholar
  6. [6]
    W. Zhang, M. Froba, J. Wang, P. Tanev, J. Wong and T. Pinnavaia, J. Am. Chem. Soc. 118 (1996) 9164.Google Scholar
  7. [7]
    J. Fu, D. Yin, D. Yin, Q. Li, L. Zhang and Y. Zhang, Microporous Mesoporous Mater. 29 (1999) 351.Google Scholar
  8. [8]
    V. R. Choudhary, M. G. Parande and P. H. Brahme, Ind. Eng. Chem. Fundam. 21 (1982) 472.Google Scholar
  9. [9]
    B. Natori, Stud. Surf. Sci. Catal. 37 (1987) 413.Google Scholar
  10. [10]
    M. R. Bocuti, K. M. Rao, A. Zecchina, G. Leofanti and G. Petrini, Stud. Surf. Sci. Catal. 48 (1989) 133.Google Scholar
  11. [11]
    R. J. Sudhakar and R. Kumar, J. Catal. 130 (1991) 440.Google Scholar
  12. [12]
    D. Mandelli, C. A. M. van Vliet, R. A. Sheldon and U. Schuchardt, Appl. Catal. 219 (2001) 209.Google Scholar
  13. [13]
    C. Coperet, H. Adolfsson and K. B. Sharpless, Chem. Commun. (1997) 1565.Google Scholar

Copyright information

© Plenum Publishing Corporation 2003

Authors and Affiliations

  1. 1.Chemical Engineering DivisionNational Chemical LaboratoryPuneIndia
  2. 2.Department of Applied ChemistryRoyal Melbourne Institute of TechnologyMelbourneAustralia

Personalised recommendations