Paper
Catalysis Science & Technology
Drs. Yuanyuan Li and Nebojsa Marinkovic for their help with
synchrotron measurements.
Notes and references
1 R. Grasselli, J. Burrington, D. Buttrey, P. DeSanto Jr.,
C. Lugmair, A. Volpe Jr. and T. Weingand, Top. Catal.,
2003, 23, 5–22.
2 R. K. Grasselli, Proceedings of the DGMK Conference, 2001,
Hamburg, Germany, p. 147.
3 T. S. R. P. Rao and K. R. Krishnamurthy, J. Catal., 1985, 95,
209–219.
4 R. K. Grasselli and H. F. Hardman, U. S. Patent 3642930, 1972.
5 R. K. Grasselli, D. D. Suresh and H. F. Hardman, U. S. Patent
4001317, 1977; R. K. Grasselli, D. D. Suresh and A. F. Miller,
U. S. Patent 4167494, 1979.
6 G. W. Keulks, L. D. Krenzke and T. M. Notermann, in
Advances in Catalysis, ed. H. P. D. D. Eley and B. W. Paul,
Academic Press, 1979, vol. 27, pp. 183–225.
7 I. B. Annenkova, T. G. Alkazov and M. S. Belenku, Kinet.
Catal., 1969, 10, 1305–1311.
8 P. A. Batist, C. G. M. van de Moesdijk, I. Matsuura and
G. C. A. Schuit, J. Catal., 1971, 20, 40–57.
Fig. 6 A schematic model of the Fe–Mo–Bi catalyst showing the role
of the Fe3+/Fe2+ redox couple during the propylene catalytic
ammoxidation process. Propylene, C3H6, is converted into the target
compound, C3H3N, on bismuth molybdate through H-abstraction and
lattice O-incorporation, while iron molybdate (including ferric and
ferrous) facilitates dioxygen dissociation and lattice oxygen transfer.
Two highlighted strategies proposed here are the introduction of the
Cr3+/Cr2+ redox couple in the catalyst preparation and replenishment
of MoO3 via a separate component or compound during the reaction
process.
9 M. W. J. Wolfs, Ph.D. thesis, Selective Oxidation of Olefins
over Multicomponent Molybdate Catalysts. Technische Hoge
School, Eindhoven 1974; I. Matsuura and M. W. J. Wolfs,
J. Catal., 1975, 37, 174–178.
5. Summary and conclusions
In our Fe–Mo–Bi catalysts, an iron molybdate phase identi-
fied as Fe2(MoO4)3 has undergone dramatic partial (more
than 60%) decomposition with increasing reaction time. This
decomposition is a one-step transformation from Fe3+ into
another form of iron molybdate, namely FeMoO4, with an
iron charge state of +2. These results were obtained by a com-
bination of Raman spectroscopy and XANES spectroscopy
studies of the fresh and spent catalysts at different reaction
times. DR-UV-vis measurements revealed a small fraction
(less than 5 volume%) of Fe2O3 during the reaction process.
The combination of these measurements allowed us to pro-
pose a mechanism of transformation of iron molybdate and
its role in the propylene ammoxidation process. This work
highlights the critical role of Fe3+ species for the stable and
efficient conversion of propylene to acrylonitrile in selective
ammoxidation. A modification of the Fe–Mo–Bi catalyst that
will help stabilize Fe3+ ions is proposed.
10 P. A. G. Van Oeffelen, Ph.D. thesis, Selective Oxidation of
Olefins on Molybdate Catalysts, Technische Hoge School,
Eindhoven, 1978.
11 P. A. Batist, Surf. Technol., 1979, 9, 443–446.
12 M. W. J. Wolfs and P. H. A. Batist, J. Catal., 1974, 32, 25–36.
13 A. P. V. Soares, M. F. Portela, A. Kiennemann and L. Hilaire,
Chem. Eng. Sci., 2003, 58, 1315–1322.
14 N. Pernicone, Catal. Today, 1991, 11, 85–91.
15 N. Burriesci, F. Garbassi, M. Petrera, G. Petrini and
N. Pernicone, in Studies in Surface Science and Catalysis,
ed. B. Delmon and G. F. Froment, Elsevier, 1980, vol. 6,
pp. 115–126.
16 S. Bordiga, E. Groppo, G. Agostini, J. A. van Bokhoven and
C. Lamberti, Chem. Rev., 2013, 113, 1736–1850; I. E. Wachs
and C. A. Roberts, Chem. Soc. Rev., 2010, 39, 5002–5017.
17 R. A. Schoonheydt, Chem. Soc. Rev., 2010, 39, 5051–5066;
F. Cesano, S. Bertarione, A. Piovano, G. Agostini, M. M. Rahman,
E. Groppo, F. Bonino, D. Scarano, C. Lamberti, S. Bordiga,
L. Montanari, L. Bonoldi, R. Millini and A. Zecchina, Catal.
Sci. Technol., 2011, 1, 123–136.
Acknowledgements
AIF acknowledges support from the Chemical Sciences,
Geosciences, and Biosciences Division, Office of Basic Energy
Sciences, Office of Science, U. S. Department of Energy (grant
no. DE-FG02-03ER15476). Use of the NSLS is supported by
the U.S. Department of Energy, Office of Science, Office of
Basic Energy Sciences under contract no. DE-AC02-98CH10886.
Beamline X19A at the NSLS is supported in part by the
Synchrotron Catalysis Consortium, U.S. Department of
Energy (grant no. DE-FG02-05ER15688). We are grateful to
18 G. Waychunas, M. Apted and G. Brown Jr., Phys. Chem.
Miner., 1983, 10, 1–9.
19 A. Patlolla, P. Baumann, W. Xu, S. D. Senanayake,
J. A. Rodriguez and A. I. Frenkel, Top. Catal., 2013, 56,
896–904.
20 Q. Xu, G. Jia, J. Zhang, Z. Feng and C. Li, J. Phys. Chem. C,
2008, 112, 9387–9393.
21 R. K. Grasselli, Catal. Today, 1999, 49, 141; R. K. Grasselli,
Appl. Catal., 1985, 15, 127–139.
2518 | Catal. Sci. Technol., 2014, 4, 2512–2519
This journal is © The Royal Society of Chemistry 2014