Catalysis Letters

, Volume 23, Issue 3–4, pp 339–351 | Cite as

A molecular level mechanism ofn-butane oxidation to maleic anhydride over vanadyl pyrophosphate

  • Pradyot A. Agaskar
  • Lorenzo De Caul
  • Robert K. Grasselli


A molecular level mechanism is proposed for the highly selective 14-e oxidative transformation ofn-butane to maleic anhydride on the surface of vanadyl pyrophosphate. The mechanism suggests that the dimeric active sites assume at any given time, one of four possible interconvertible states which differ from each other in the number of available oxygen atoms and the formal oxidation states of the individual vanadium atoms. The relative ratios of active sites in each of the four possible states are dictated by the reaction conditions, the redox properties of the reacting gases and the structure of the vanadyl pyrophosphate active surface. A crucial feature of the mechanism is a “pseudo-ozonide” surface species formed by the interaction of a chemisorbed dioxygen molecule and an adjacent metal-oxo group. This unusual species is responsible for the initial activation of then-butane, which occurs when the chemisorbed dioxygen abstracts an H-atom from the alkane and the adjacent metal-oxo group reacts with the incipient alkyl radical to form an alkoxy group. The proposed mechanism is entirely consistent with literature reports describing the behaviour of (VO)2P2O7 in flow, pulse and TAP reactors.


Selective oxidation n-butane maleic anhydride (VO)2P2O7  mechanism site isolation 


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  1. [1]
    G. Centi, Catal. Today 16 (1993) 1.Google Scholar
  2. [2]
    G. Centi, F. Trifiró, J.R. Ebner and V.M. Franchetti, Chem. Rev. 88 (1988) 55.Google Scholar
  3. [3]
    G. Busca, G. Centi and F. Trifiro, Appl. Catal. 25 (1986) 265.Google Scholar
  4. [4]
    J. Ziolkowski, E. Bordes and P. Courtine, J. Catal. 122 (1990) 126.Google Scholar
  5. [5]
    R.K. Grasselli, J. Chem. Educ. 63 (1986) 216.Google Scholar
  6. [6]
    J.R. Ebner and M.R. Thompson, in:Studies in Surface Science and Catalysis, Vol. 67 (Elsevier, Amsterdam, 1991) p. 31.Google Scholar
  7. [7]
    K. Inumaru, T. Okuhara and M. Misono, Chem. Lett. (1992) 1955.Google Scholar
  8. [8]
    J.L. Callahan and R.K. Grasselli, AIChE9 (1963) 755.Google Scholar
  9. [9]
    J.R. Ebner and J.T. Gleaves, in:Oxygen Complexes and Oxygen Activation by Transition Metals, eds. A.E. Martell and D.T. Sawyer (Plenum Press, New York, 1988) p. 273.Google Scholar
  10. [10]
    B. Schiøtt, K.A. Jørgensen and R. Hoffmann, J. Phys. Chem. 95 (1991) 2297.Google Scholar
  11. [11]
    M.A. Pepera, J.L. Callahan, M.J. Desmond, E.C. Milberger, P.R. Blum and N.J. Bremer, J. Am. Chem. Soc. 107 (1985) 4883.Google Scholar
  12. [12]
    H.S. Horowitz, C.M. Blackstone, A.W. Sleight and G. Teufer, Appl. Catal. 38 (1988) 193.Google Scholar
  13. [13]
    J.S. Jung, E. Bordes and P. Courtine, in:Studies in Surface Science and Catalysis, Vol. 21 (Elsevier, Amsterdam, 1985) p. 345.Google Scholar
  14. [14]
    J.R. Ebner and M.R. Thompson, Catal. Today 16 (1993) 51.Google Scholar
  15. [15]
    R.S. Drago and R.H. Beer, Inorg. Chim. Acta 198-200 (1992) 359.Google Scholar
  16. [16]
    J.T. Gleaves, J.R. Ebner and T.C. Kuechler, Catal. Rev.-Sci. Eng. 30 (1988) 49.Google Scholar
  17. [17]
    A. Aguero, R.P.A. Sneeden and J.C. Volta, in:Heterogeneous Catalysis and Fine Chemicals, ed. M. Guisnet (Elsevier, Amsterdam, 1988) p. 353.Google Scholar
  18. [18]
    G. Centi, G. Golinelli and G. Busca, J. Phys. Chem. 94 (1990) 6813.Google Scholar
  19. [19]
    J. March,Advanced Organic Chemistry (Wiley, New York, 1985) p. 967.Google Scholar
  20. [20]
    B. Schiøtt and K.A. Jørgensen, in:Dioxygen Activation and Homogeneous Catalytic Oxidation, ed. L.I. Simandi (Elsevier, Amsterdam, 1991) p. 655.Google Scholar
  21. [21]
    R.M. Contractor and A.W. Sleight, Catal. Today 3 (1988) 175.Google Scholar
  22. [22]
    F. Cavani, G. Centi, F. Triffirò and R.K. Grasselli, Catal. Today 3 (1988) 185.Google Scholar

Copyright information

© J.C. Baltzer AG, Science Publishers 1994

Authors and Affiliations

  • Pradyot A. Agaskar
    • 1
  • Lorenzo De Caul
    • 1
  • Robert K. Grasselli
    • 1
  1. 1.Mobil R&D CorporationCentral Research LaboratoryPrincetonUSA

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