Journal of Porous Materials

, Volume 17, Issue 3, pp 265–274 | Cite as

Sol–gel derived mesoporous Cr/Al2O3 catalysts for SCR of NO by ammonia

  • F. Ayari
  • M. Mhamdi
  • G. Delahay
  • A. Ghorbel


Catalytic performances of Cr/Al2O3 catalysts were investigated in Selective Catalytic Reduction (SCR) of NO by NH3 in the presence of oxygen. Solids were prepared either by sol–gel method or by impregnation and were characterized by different techniques such as chemical analysis, N2 physisorption, XRD, 27Al MAS NMR, DRIFT, UV–Vis Diffuse Reflectance (DRS), Raman Spectroscopy and Temperature Programmed Reduction by H2 (H2-TPR). The physisorption of N2 at 77 K reveals that solids are mesoporous. On the other hand, XRD shows that xerogels are amorphous but supercritical drying leads to a nanosized crystallite state. No crystalline α-Cr2O3 was found which indicate that metal species reside essentially on the surface of Al2O3 and their size measured less than 4 nm. Furthermore, 27Al MAS NMR reveals that part of chromium ions occupies sites on/in Al2O3 in close vicinity of tetrahedral 27Al. This, apparently, is not the case for aerogels. DRIFT results show that there is a consumption of hydroxyl groups of alumina after calcination. The esterification reaction between hydroxyl groups and chromium oxide during calcination leads to the formation of anchored (poly-)chromates according to DRS, Raman, and H2-TPR results. The catalysts are active in the studied reaction by NH3 and the activity is principally governed by preparation method and operating conditions. When compared to xerogels, aerogels are more active in NO reduction and less selective toward N2O. Preparation method and drying mode seem to involve the predominance of active species which are essentially mono and polychromates but Cr3+ ions incorporated inside alumina seem to be inactive.


Chromium Alumina Sol–gel SCR of NO by NH3 


  1. 1.
    G.J.K. Acres, B. Harrison, Top. Catal. 28, 141 (2004). doi: 10.1023/B:TOCA.0000024329.85506.94 CrossRefGoogle Scholar
  2. 2.
    A. Fritz, V. Pitchon, Appl. Catal. B: Environ. 13, 1 (1997)CrossRefGoogle Scholar
  3. 3.
    H. Bosch, F. Janssen, Catal. Today 2, 369 (1988). doi: 10.1016/0920-5861(88)80001-4 CrossRefGoogle Scholar
  4. 4.
    J.H.A. Kiel, A.C.S. Edelaar, W. Prins, W.P.M. van Swaaij, Appl. Catal. B: Environ. 1, 41 (1992)CrossRefGoogle Scholar
  5. 5.
    H. Niyama, K. Murata, A. Ebitani, E. Echigoya, J. Catal. 48, 194 (1977). doi: 10.1016/0021-9517(77)90090-2 CrossRefGoogle Scholar
  6. 6.
    H. Niyama, K. Murata, E. Echigoya, J. Catal. 48, 201 (1977). doi: 10.1016/0021-9517(77)90091-4 CrossRefGoogle Scholar
  7. 7.
    H.E. Curry-Hyde, A. Baiker, Ind. Eng. Chem. Res. 29, 1985 (1990). doi: 10.1021/ie00106a001 CrossRefGoogle Scholar
  8. 8.
    H.E. Curry-Hyde, H. Musch, A. Baiker, Appl. Catal. 65, 211 (1990). doi: 10.1016/S0166-9834(00)81598-5 CrossRefGoogle Scholar
  9. 9.
    H.E. Curry-Hyde, H. Musch, M. Schrame-Marth, A. Wokaun, A. Baiker, J. Catal. 133, 397 (1992). doi: 10.1016/0021-9517(92)90249-H CrossRefGoogle Scholar
  10. 10.
    H. Schneider, U. Scharf, A. Wokaun, A. Baiker, J. Catal. 147, 145 (1994)Google Scholar
  11. 11.
    B.L. Duffy, H.E. Curry-Hyde, N.W. Cant, P.F. Nelson, J. Catal. 149, 11 (1994). doi: 10.1006/jcat.1994.1268 CrossRefGoogle Scholar
  12. 12.
    C. Fountzoula, H.K. Matralis, C. Papadopoulou, G.A. Voyiatzis, C. Kordulis, J. Catal. 172, 391 (1997). doi: 10.1006/jcat.1997.1845 CrossRefGoogle Scholar
  13. 13.
    H. Zarrouk, A. Ghorbel, G.M. Pajonk, S.J. Teichner, in Proc 9th Ibero Americain Symposium on Catalysis, Lisbon, 16–21 July, 1984, p. 339Google Scholar
  14. 14.
    A. Sayari, A. Ghorbel, G.M. Pajonk, S.J. Teichner, Bull. Soc. Chim. Fr. 5-6(part I), 220 (1981)Google Scholar
  15. 15.
    S. Zine, A. Sayari, A. Ghorbel, Can. J. Chem. Eng. 65, 127 (1987). doi: 10.1002/cjce.5450650120 CrossRefGoogle Scholar
  16. 16.
    S. Zine, A. Ghorbel, in The 2nd International Symposium of Heterogeneous Catalysis and Fine Chemicals, Poitiers, 2–5 October, 1990, p. 455Google Scholar
  17. 17.
    Y. Kadri, A. Ghorbel, C. Naccache, J. Chim. Phys. 94, 1993 (1995)Google Scholar
  18. 18.
    Y. Kadri, A. Ghorbel, A. Rives, R. Hubaut, J. Chem. Soc. Faraday Trans. 94, 455 (1998). doi: 10.1039/a705555b CrossRefGoogle Scholar
  19. 19.
    F. Ayari, M. Mhamdi, G. Delahay, A. Ghorbel, J. Sol–gel Sci. Technol. 49, 170 (2009). doi: 10.1007/s10971-008-1860-7 CrossRefGoogle Scholar
  20. 20.
    M.A. Siddiqi, R.A. Siddiqui, B. Atakan, Surf. Coat. Tech. 201, 9055 (2007). doi: 10.1016/j.surfcoat.2007.04.036 CrossRefGoogle Scholar
  21. 21.
    P.P. Semyannikov, I.K. Igumenov, S.V. Trubin, T.P. Chusova, Z.I. Semenova, Thermochim. Acta 432, 91 (2005). doi: 10.1016/j.tca.2005.02.034 CrossRefGoogle Scholar
  22. 22.
    S. Brunauer, L. Deming, W. Deming, E.J. Teller, J. Am. Chem. Soc. 62, 1723 (1940). doi: 10.1021/ja01864a025 CrossRefGoogle Scholar
  23. 23.
    J.H. DeBoer, B.C. Lippens, J. Catal. 3, 38 (1946). doi: 10.1016/0021-9517(64)90090-9 CrossRefGoogle Scholar
  24. 24.
    H. Xiong, Y. Zhang, S. Wang, J. Li, Catal. Commun. 6, 512 (2005). doi: 10.1016/j.catcom.2005.04.018 CrossRefGoogle Scholar
  25. 25.
    M. Afzal, F. Mahmood, Collect. Czech. Chem. Commun. 58, 474 (1993). doi: 10.1135/cccc19930474 CrossRefGoogle Scholar
  26. 26.
    A.K. Khattak, M. Afzal, M. Saleem, G. Yasmeen, R. Ahmad, Colloids Surf. A Physicochem. Eng. Asp. 162, 99 (2000). doi: 10.1016/S0927-7757(99)00218-6 CrossRefGoogle Scholar
  27. 27.
    G. Buelna, Y.S. Lin, Microporous Mesoporous Mater. 30, 359 (1999). doi: 10.1016/S1387-1811(99)00065-7 CrossRefGoogle Scholar
  28. 28.
    K. Wefers, C. Mirsa, Oxides and Hydroxides of Aluminum, Alcoa Technical Paper No. 19, Alcoa Laboratories (1987)Google Scholar
  29. 29.
    J.W. Akitt, in Multinuclear NMR, ed. by J. Mason (Plenum, New York, 1987), Chapter 9Google Scholar
  30. 30.
    A.T. Bell, A. Pines, NMR Techniques in Catalysis (Dekker, New York, 1994)Google Scholar
  31. 31.
    S. Acosta, R. Corria, D. Leclercq, P.H. Mutin, A. Vioux, Sol–gel Sci. Technol. 2, 25 (1994). doi: 10.1007/BF00486208 CrossRefGoogle Scholar
  32. 32.
    Y. Jaymes, A. Douy, P. Florian, D. Massiot, J.P. Loutures, Sol–gel Sci. Technol. 2, 367 (1994). doi: 10.1007/BF00486272 CrossRefGoogle Scholar
  33. 33.
    B.M. Weckhuysen, L.M. De Ridder, R.J. Grobet, R.A. Schoonheydt, J. Phys. Chem. 99, 320 (1995). doi: 10.1021/j100001a048 CrossRefGoogle Scholar
  34. 34.
    A. Abragam, The Principles of Nuclear Magnetism (Clarendon Press, Oxford, 1961)Google Scholar
  35. 35.
    N. Bloembergen, Physica 15, 386 (1949). doi: 10.1016/0031-8914(49)90114-7 CrossRefGoogle Scholar
  36. 36.
    A. Carrington, A.D. McLachlan, Introduction to Magnetic Resonance (Harper & Row, New York, 1967)Google Scholar
  37. 37.
    E. Heracleous, A.A. Lemonidou, J.A. Lercher, Appl. Catal. A 264, 73 (2004). doi: 10.1016/j.apcata.2003.12.030 CrossRefGoogle Scholar
  38. 38.
    C.C.S. Macedo, F.R. Abreu, A.P. Tavares, M.B. Alves, L.F. Zara, J.C. Rubima, P.A.Z. Suarez, J. Braz. Chem. Soc. 17, 1291 (2006). doi: 10.1590/S0103-50532006000700014 CrossRefGoogle Scholar
  39. 39.
    B.M. Weckhuysen, I.E. Wachs, R.A. Schoonheydt, Chem. Rev. 96, 3327 (1996). doi: 10.1021/cr940044o CrossRefGoogle Scholar
  40. 40.
    Z.G. Szabo, K. Kamaras, S. Szebeni, I. Ruff, Specrochim. Acta 34a, 607 (1978). doi: 10.1016/0584-8539(78)80059-2 CrossRefGoogle Scholar
  41. 41.
    B.M. Weckhuysen, L.M. De Ridder, R.A. Schoonheydt, J. Phys. Chem. 97, 4756 (1993). doi: 10.1021/j100120a030 CrossRefGoogle Scholar
  42. 42.
    F. Cavani, M. Koutyrev, F. Trifirò, A. Bertolini, D. Ghisletti, R. Iezzi, A. Santucci, G. Del Piero, J. Catal. 158, 236 (1996). doi: 10.1006/jcat.1996.0023 CrossRefGoogle Scholar
  43. 43.
    R. Puurunen, B.M. Weckhuysen, J. Catal. 210, 418 (2002). doi: 10.1006/jcat.2002.3686 CrossRefGoogle Scholar
  44. 44.
    B.M. Weckhuysen, R.A. Schoonheydt, J.M. Jehng, I.E. Wachs, S.J. Cho, R. Ryoo, S. Kijlstra, E. Poels, J. Chem. Soc. Faraday Trans. 91, 3245 (1995). doi: 10.1039/ft9959103245 CrossRefGoogle Scholar
  45. 45.
    A. Cimino, D. Cordischi, S. De Rossi, G. Ferraris, D. Gazzoli, V. Indovina, M. Occhiuzzi, M. Valigi, J. Catal. 127, 761 (1991). doi: 10.1016/0021-9517(91)90197-C CrossRefGoogle Scholar
  46. 46.
    F.D. Hardcastle, I.E. Wachs, J. Mol. Catal. 46, 173 (1988). doi: 10.1016/0304-5102(88)85092-2 CrossRefGoogle Scholar
  47. 47.
    D.H. Cho, S.D. Yim, G.H. Cha, J.S. Lee, Y.G. Kim, J.S. Chung, I.S. Nam, J. Phys. Chem. A 102, 7913 (1998). doi: 10.1021/jp981927c CrossRefGoogle Scholar
  48. 48.
    S.D. Yim, D.J. Koh, I.S. Nam, Y.G. Kim, Catal. Lett. 64, 201 (2000). doi: 10.1023/A:1019076112539 CrossRefGoogle Scholar
  49. 49.
    O.F. Gorriz, L.E. Cadús, Appl. Catal. A 180, 247 (1999). doi: 10.1016/S0926-860X(98)00344-5 CrossRefGoogle Scholar
  50. 50.
    M. Cherian, M.S. Rao, A.M. Hirt, I.E. Wachs, G. Deo, J. Catal. 211, 482 (2002)Google Scholar
  51. 51.
    A.B. Gaspar, J.L.F. Brito, L.C. Dieguez, J. Mol. Catal. Chem. 203, 251 (2003). doi: 10.1016/S1381-1169(03)00381-9 CrossRefGoogle Scholar
  52. 52.
    A.B. Gaspar, L.C. Dieguez, Appl. Catal. 227, 241 (2002). doi: 10.1016/S0926-860X(01)00942-5 CrossRefGoogle Scholar
  53. 53.
    B.M. Weckhuysen, A.A. Verberckmoes, A.R. De Baets, R.A. Schoonheydt, J. Catal. 166, 160 (1997). doi: 10.1006/jcat.1997.1518 CrossRefGoogle Scholar
  54. 54.
    D. Shi, Z. Zhao, C. Xu, A. Duan, J. Liu, T. Dou, J. Mol. Catal. Chem. 245, 106 (2006). doi: 10.1016/j.molcata.2005.09.031 CrossRefGoogle Scholar
  55. 55.
    J.H. Hillier, V.R. Saunders, Chem. Phys. Lett. 9, 219 (1971). doi: 10.1016/0009-2614(71)85034-0 CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Laboratoire de Chimie des Matériaux et Catalyse, Département de Chimie, Faculté des Sciences de TunisTunisTunisia
  2. 2.Institut Charles Gerhardt Montpellier, UMR 5253, CNRS-UM2-ENSCM-UM1, Eq. “Matériaux Avancés pour la Catalyse et la Santé”, ENSCM (MACS – Site la Galéra)Montpellier Cedex 5France

Personalised recommendations