Abstract
The mechanism of catalytic oxidation reactions was studied using in situ X-ray absorption spectroscopy (XAFS) over a 17.5 wt% V2O5/Al2O3 catalyst, i.e., at reaction temperatures and in the presence of reactants. It was found that X-ray absorption near-edge structure (XANES) is a powerful tool to study changes in the local environment and the oxidation state of the vanadium centres during catalytic oxidation. At 623 K, the catalyst follows the associative mechanism in CO oxidation. XAFS revealed that the Mars–van Krevelen mechanism is operative at 723 K for CO oxidation. The extended X-ray absorption fine structure (EXAFS) results showed that the structure of the supported V2O5 phase consists of monomeric tetrahedral (Al–O)3–V=O units after dehydration in air at 623 K. However, the residuals of the EXAFS analysis indicate that an extra contribution has to be accounted for. This contribution probably consists of polymeric vanadate species. The structure remains unchanged during steady-state CO oxidation at 623 and 723 K. Furthermore, when oxygen was removed from the feed at 623 K, no changes in the spectra occurred. However, when oxygen is removed from the feed at 723 K, reduction of the vanadium species was observed, i.e., the vanadyl oxygen atom is removed. The V3+ ion subsequently migrates into the γ-Al2O3 lattice, where it is positioned at an Al3+ octahedral position. This migration process appears to be reversible; so the (Al–O)3–V=O units are thus restored by re-oxidation.
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X. Gao, S.R. Bare, B.M. Weckhuysen and I.E. Wachs, J. Phys. Chem. B 102 (1998) 10842.
I.E. Wachs, Catal. Today 27 (1996) 437.
G.T. Went and S.T. Oyama, J. Phys. Chem. 94 (1990) 4240.
F. Roozeboom, M.C. Mittelmeijer-Hazeleger, J.A. Moulijn, J. Medema, V.H.J. de Beer and P.J. Gellings, J. Phys. Chem. 84 (1980) 2783.
G. Busca, Mater. Chem. Phys. 19 (1988) 157.
A.A. Davydov, Kinet. Katal. 34 (1993) 951.
T. Tanaka, H. Yamashita, R. Tsuchitani, T. Funabiki and S. Yoshida, J. Chem. Soc. Faraday Trans. I 84 (1988) 2987.
S. Yoshida, T. Tanaka, Y. Nishimura, H. Mizutani and T. Funabiki, Proc. ICC IX (1988) p. 1473.
S. Yoshida, T. Tanaka, T. Hanada, T. Hiraiwa and H. Kanai, Catal. Lett. 12 (1992) 277.
R. Kozlowski, R.F. Pettifer and J.M. Thomas, J. Phys Chem. 87 (1983) 5176.
J. Haber, A. Kozlowska and R. Kozlowski, J. Catal. 102 (1986) 52.
N. Das, H. Eckert, H. Hu, I.E. Wachs, J.F. Walzer and F.J. Feher, J. Phys. Chem. 97 (1993) 8240.
H. Eckert and I.E. Wachs, Mater. Res. Soc. Symp. Proc. 111 (1988) 455.
H. Eckert and I.E. Wachs, J. Phys. Chem. 93 (1989) 6796.
L.R. Le Costumer, B. Taouk, M. Le Meur, E. Payen, M. Guelton and J.M. Grimblot, J. Phys. Chem. 92 (1988) 1230.
B.M. Weckhuysen, I.P. Vannijvel and R.A. Schoonheydt, Zeolites 15 (1995) 482.
U. Scharf, M. Schraml-Merth, A. Wokaun and A. Baiker, J. Chem. Soc. Faraday Trans. 87 (1991) 3299.
G. Catana, R. Ramachandra Rao, B.M. Weckhuysen, P. van der Voort, E. Vansant and R. Schoonheydt, J. Phys. Chem. B 102 (1998) 8005.
M.F. Hazenkamp and G. Blasse, J. Phys. Chem. 96 (1992) 3442.
M. Anpo, M. Sunamoto and M. Che, J. Phys. Chem. 93 (1989) 1187.
G. Busca and E. Giamello, Mater. Chem. Phys. 25 (1990) 475.
B.I. Wittington and J.R. Anderson, J. Phys. Chem. 97 (1993) 1032.
J.M. Jehng, G. Deo, B.M. Weckhuysen and I.E. Wachs, J. Mol. Catal. A 110 (1996) 41.
I.E. Wachs and B.M. Weckhuysen, Appl. Catal. A 157 (1997) 67.
S.S. Chan, I.E. Wachs, L.L. Murrell, L. Wang and W.K. Hall, J. Phys. Chem. 88 (1984) 5831.
X. Gao, S.R. Bare, B.M. Weckhuysen and I.E. Wachs, J. Phys. Chem. B 102 (1998) 10684.
T. Kataoka and J.A. Dumesic, J. Catal. 112 (1988) 66.
G.C. Bond, J. Perez Zurita, S. Flamerz, P.J. Gellings, H. Bosch, J.G. van Ommen and B.J. Kip, Appl. Catal. 22 (1986) 361.
W. Fluhr, M. Schraml-Marth, A. Wokaun and A. Baiker, Ber. Bunsenges Phys. Chem. 8 (1989) 852.
I.E. Wachs, G. Deo, B.M. Weckhuysen, V.V. Guliants and J.B. Benziger, Catal. Today 32 (1996) 47.
G. Ramis, C. Cristiani, P. Forzatti and G. Busca, J. Catal. 124 (1990) 574.
I.E. Wachs, R.Y. Saleh, S.S. Chan and C.C. Chersich, Appl. Catal. 15 (1985) 339.
K. Mori, M. Inomata, A. Miyamoto and Y. Murakami, J. Chem. Soc. Faraday Trans. I 80 (1984) 2666.
T. Tanaka, Y. Nishimura, S. Kawasaki, M. Oe, T. Funabiki and S. Yoshida, J. Catal. 118 (1989) 327.
S.L. Kaliaguine, B.N. Shelimov and B. Kazansky, J. Catal. 55 (1978) 384.
A.A. Siddiqi and J.W. Tenini, Hydrocarbon Process. 60 (1984) 649.
M. Iwamoto, J. Hirata, K. Matsukami and S. Kagawa, J. Phys. Chem. 87 (1983) 903.
G.I. Golodets, Stud. Surf. Sci. Catal. 55 (1990) 693.
P. Mars and D.W. van Krevelen, Chem. Eng. Sci. (Special Suppl.) 3 (1954) 41.
A.J. Van Dillen, Catalytic oxidation of carbon monoxide over oxides of indium and vanadium, Thesis, Utrecht University (1977).
L.V. Azararoff and D.M. Pease, in: X-Ray Spectroscopy, ed. L.V. Azaroff (McGraw Hil, New York, 1974).
J. Wong, F.W. Lytle, R.P. Mesmer and D.H. Maylotte, Phys. Rev. B 30 (1984) 5596.
J. Wong, R.P. Mesmer, D.H. Maylotte and F.W. Lytle, in: EXAFS and Near Edge Structure, eds. A. Bianconi, L. Inoccia and S. Stipcich (Springer, Berlin, 1983) p. 130.
J. Wong, D.H. Maylotte, F.W. Lytle, R.B. Greegor and R.L. St. Peters, in: EXAFS and Near Edge Structure, eds. A. Bianconi, L. Inoccia and S. Stipcich (Springer, Berlin, 1983) p. 206.
I. Davoli, S. Stizza, M. Benfatto, O. Gzowski, L. Murawski and A. Bianconi, in: EXAFS and Near Edge Structure, eds. A. Bianconi, L. Inoccia and S. Stipcich (Springer, Berlin, 1983) p. 162.
M. Ruitenbeek, R.A. Overbeek, A.J. van Dillen, D.C. Koningsberger and J.W. Geus, Recl. Trav. Chim. Pays-Bas 115 (1996) 519.
J. van den Berg, Stoichiometry and catalytic activity of vanadia-based oxides for the oxidation of CO and H2, Thesis, Utrecht University (1984).
I.E. Wachs, J.-M. Jehng, G. Deo, B.M. Weckhuysen, V.V. Guliants, J.B. Benziger and S. Sundaresan, J. Catal. 170 (1997) 75.
F.W.H. Kampers, T.M.J. Maas, J. van Grondelle, P. Brinkgreve and D.C. Koningsberger, Rev. Sci. Instrum. 60 (1989) 2635.
M. Vaarkamp, B.L. Mojet, F.S. Modica, J.T. Miler and D.C. Koningsberger, J. Phys. Chem. 99 (1995) 16067.
http://www.xs4all.nl/_xsi/.
M. Vaarkamp, I. Dring, R.J. Oldman, E.A. Stern and D.C. Koningsberger, Phys. Rev. B 50 (1994) 7872.
J.W. Cook, Jr. and D.E. Sayers, J. Appl. Phys. 52 (1981) 5024.
J.B.A.D. van Zon, D.C. Koningsberger, H.F.J. van' t Blik and D.E. Sayers, J. Chem. Phys. 82 (1985) 5742.
E. Vogt, Preparation and properties of catalysts supported on modified silica, Thesis, Utrecht University (1988).
B.L. Mojet, Metal support interactions, a step closer to the origin, Thesis, Utrecht University (1997).
F.W.H. Kampers, EXAFS in catalysis, instrumentation and applications, Thesis, TU Eindhoven (1988).
J.N. Fiedor, A. Proctor, M. Houalla and D.M. Hercules, Surf. Interface Anal. 20 (1993) 1.
S.J. Scierka, A. Proctor, J.N. Fiedor and D.M. Hercules, Surf. Interface Anal. 20 (1993) 901.
M.A. Eberhardt, A. Proctor, M. Houalla and D.M. Hercules, J. Catal. 160 (1996) 27.
M.J. Fay, A. Proctor, D.P. Hoffmann, M. Houalla and D.M. Hercules, Mikrochim. Acta 109 (1992) 281.
E.R. Malinowski, Factor Analysis in Chemistry, 2nd Ed. (Wiley, New York, 1991).
E.R. Malinowski, J. Chemom. 3 (1988) 49.
E.R. Malinowski, J. Chemom. 4 (1990) 102.
F.M. Dautzenberg, ACS Symposium Series 421 (1989) 277.
M. Ruitenbeek, Characterisation of vanadium-based oxidation catalysts, Thesis, Utrecht University (1999).
D.E. Ramaker, B.L. Mojet, D.C. Koningsberger and W.E. O'Grady, J. Phys. Condens. Matter 10 (1998) 8753.
F.M.F. de Groot, M. Ruitenbeek and D.C. Koningsberger, to be published.
H. Praliaud and M.-V. Mathieu, J. Chim. Phys. 73 (1976) 689.
F. Lemoigno, E. Prouzet, Z.Y. Wu, P. Gressier and G. Ouvrard, J. Phys. IV France 7 (1997) 263.
W.A. Caliebe, C.-C. Kao, J.B. Hastings, M. Taguchi, A. Kotani, T. Uozumi and F.M.F. de Groot, Phys. Rev. B 58 (1998) 13452.
J. Haber, in: Catalytic Oxidation, Principles and Applications, eds. R.A. Sheldon and R.A. van Santen (World Scientific, London, 1995) p. 17.
R.E. Newnham and Y.M. de Haan, Z. Kristall. 117 (1962) 235.
N.W. Hurst, S.J. Gentry, A. Jones and B.D. McNicol, Catal. Rev. Sci. Eng. 24 (1982) 233.
W.S. Xia, H.L. Wan and Y. Chen, J. Mol. Catal. A 138 (1999) 185.
B.M. Weckhuysen, L.M. de Ridder, P.J. Grobet and R.A. Schoonheydt, J. Phys. Chem. 99 (1995) 320.
B.M. Weckhuysen and R.A. Schoonheydt, Catal. Today 51 (1999) 223.
A.F. Reid and T.M. Sabine, J. Solid State Chem. 2 (1970) 203.
B. Reuter, R. Aust, G. Collsmann and Ch. Neuwald, Z. Anorg. Allg. Chem. 500 (1983) 188.
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Ruitenbeek, M., van Dillen, A., de Groot, F. et al. The structure of vanadium oxide species on γ-alumina; an in situ X-ray absorption study during catalytic oxidation. Topics in Catalysis 10, 241–254 (2000). https://doi.org/10.1023/A:1019180504770
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DOI: https://doi.org/10.1023/A:1019180504770