Reaction Kinetics, Mechanisms and Catalysis

, Volume 102, Issue 2, pp 263–282 | Cite as

Kinetics of toluene hydrogenation—integrating a dynamic approach regarding catalyst activity

  • Aqeel Ahmad Taimoor
  • Isabelle Pitault


Gas phase toluene hydrogenation is investigated over Pt/Al2O3 catalyst with temperature ranging from 75 to 125 °C and at atmospheric pressure. Strong activity variations are observed during long duration experiments. These variations are thoroughly investigated and a mechanistic model is proposed with dynamic adsorption activity of the reactants, used to explain the decrease in catalyst activity. This model considers competitive adsorption behaviour of the reactants and dissociative adsorption of hydrogen. Such a model can also be used to explain the strong metal-support interaction (SMSI) effect induced by the catalyst support. The decrease in activity after temperature maxima as previously observed can also be addressed by the approach presented. A comparison of activity variation at different residence times i.e. 20–50 kgcat·s·mol−1 and different hydrogen and toluene partial pressures is also simulated.


Toluene hydrogenation Activity variation Reaction kinetics 

List of Symbols

Alphabetical Symbols


Stoichiometric constant


Stoichiometric constant


Sites on platinum (mol·kgcat −1)


Concentration of species (mol·m−3)


Rate parameters for hydrogenation reaction


Partial pressures (Pa)


Reaction rate


Sites offered by support (mol·kgcat −1)


Temperature (K)


Time (s)



Greek Symbols


Hydrogen reaction order


Deactivation factor



Species adsorbed on platinum


Species adsorbed on support


Order of deactivation


ad, H2

Hydrogen adsorption


Toluene adsorption

d, H2

Hydrogen desorption


Toluene desorption









We are thankful to Government of Pakistan (Higher Education Commission) for supporting this research work through a doctoral grant to Aqeel Ahmad TAIMOOR.


  1. 1.
    Wang J, Wan W (2009) Int J Hydrogen Energy 34:235–244CrossRefGoogle Scholar
  2. 2.
    Das D, Veziroglu TN (2001) Int J Chem Reactor Eng 26:13–28Google Scholar
  3. 3.
    Saeys M, Reyniers MF, Thybaut JW, Neurock M, Marin GB (2005) J Catal 236:129–138CrossRefGoogle Scholar
  4. 4.
    Keane MA, Patterson PM (1996) J Chem Soc Faraday Trans 92:1413–1421CrossRefGoogle Scholar
  5. 5.
    Orozco JM, Webb G (1983) Appl Catal 6:67–84CrossRefGoogle Scholar
  6. 6.
    Rousset JL, Stievano L, Cadete Santos Aires FJ, Geantet C, Renouprez AJ, Pellarin M (2001) J Catal 197:335–343CrossRefGoogle Scholar
  7. 7.
    Kaufmann TG, Kaldor A, Stuntz GF, Kerby MC, Ansell LL (2000) Catal Today 62:77–90CrossRefGoogle Scholar
  8. 8.
    Klvana D, Chaouki J, Kusohorsky D, Chavarie C (1988) Appl Catal 42:121–130CrossRefGoogle Scholar
  9. 9.
    Gaidai NA, Kazantsev RV, Nekrasov NV, Shulga YuM, Ivleva IN (2002) React Kinet Catal Lett 75:55–61CrossRefGoogle Scholar
  10. 10.
    Kazantsev RV, Gaidai NA, Nekrasov NV, Tenchev K, Petrov L, Lapidus AL (2003) Kinet Catal 44:529–535CrossRefGoogle Scholar
  11. 11.
    Lin SD, Vannice MA (1993) J Catal 143:563–572CrossRefGoogle Scholar
  12. 12.
    Lindfors LP, Salmi T, Smeds S (1993) Chem Eng Sci 48:3813–3828CrossRefGoogle Scholar
  13. 13.
    Thybaut JW, Saeys M, Marin GB (2002) Chem Eng J 90:117–129CrossRefGoogle Scholar
  14. 14.
    Lin SD, Vannice MA (1993) J Catal 143:554–562CrossRefGoogle Scholar
  15. 15.
    Rahaman MV, Vannice MA (1991) J Catal 127:267–275CrossRefGoogle Scholar
  16. 16.
    Rahaman MV, Vannice MA (1991) J Catal 127:251–266CrossRefGoogle Scholar
  17. 17.
    Wang J, Huang L, Li Q (1998) Appl Catal A Gen 175:191–199CrossRefGoogle Scholar
  18. 18.
    Levenspiel O (1999) Chemical reaction engineering, 3rd edn. Wiley, New YorkGoogle Scholar
  19. 19.
    Masloboishchikova OV, Khelkovskaya-Sergeeva EG, Bogdan VI, Vasina TV, Kustov LM (2006) Russ J Phys Chem 80:646–652CrossRefGoogle Scholar
  20. 20.
    Castaño P, Arandes JM, Pawelec B, Luis J, Fierro G, Gutierrez A, Bilbao J (2007) Ind Eng Chem Res 46:7417–7425CrossRefGoogle Scholar
  21. 21.
    Chupin J, Gnep N, Lacombe S, Guisnet M (2001) Appl Catal A Gen 206:43–56CrossRefGoogle Scholar
  22. 22.
    Bartholomew CH (2001) Appl Catal A Gen 212:17–60CrossRefGoogle Scholar
  23. 23.
    Hallenbeck PC, Ghosh D (2009) Trends Biotechnol 27:5CrossRefGoogle Scholar
  24. 24.
    Lindfors LP, Salmi T (1993) Ind Eng Chem Res 32:34–42CrossRefGoogle Scholar
  25. 25.
    Mamède AS, Giraudon JM, Löfberg A, Leclercq L, Leclercq G (2002) Appl Catal A Gen 227:73–82CrossRefGoogle Scholar
  26. 26.
    Gaidai NA, Gudkov BS, Aliev KhKh, Kiperman SL (1992) Kinet Katal 33:370–374Google Scholar
  27. 27.
    Keane MA, Patterson PM (1999) Ind Eng Chem Res 38:1295–1305CrossRefGoogle Scholar
  28. 28.
    Bond GC (2005) Metal-catalysed reactions of hydrocarbons. Springer, New YorkGoogle Scholar
  29. 29.
    Briens C, Piskorz J, Berruti F (2008) Int J Chem Reactor Eng 6:1–49Google Scholar
  30. 30.
    Wang J, Wan W (2009) Int J Hydrogen Energy 34:3313–3323CrossRefGoogle Scholar
  31. 31.
    Ali AGA, Ali LI, Aboul-Fotouh SM, Aboul-Gheit AK (1998) Appl Catal A Gen 170:285–296CrossRefGoogle Scholar
  32. 32.
    Slioor RI, Kanervo JM, Keskitalo TJ, Krause AOI (2008) Appl Catal A Gen 344:183–190CrossRefGoogle Scholar
  33. 33.
    Slioor RI, Kanervo RI, Krause AOI (2008) Catal Lett 121:24–32CrossRefGoogle Scholar
  34. 34.
    El-Hajj A, Karaki S, Al-Husseini M, Kabalan KY (2004) Spreadsheets Educ 1:217–229Google Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2011

Authors and Affiliations

  1. 1.Laboratoire de Génie des Procédés Catalytiques LGPC—CNRS/CPE LyonVilleurbanne CedexFrance

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