Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-27T02:08:31.374Z Has data issue: false hasContentIssue false

A Kinetic Study of Hydrocarbons Reactivity on Palladium Catalysts through a DFT Approach

Published online by Cambridge University Press:  21 March 2011

Valeria Bertani
Affiliation:
Dipartimento di Chimica Fisica Applicata, Politecnico di Milano, Milano, ITALY
Carlo Cavallotti
Affiliation:
Dipartimento di Chimica Fisica Applicata, Politecnico di Milano, Milano, ITALY
Maurizio Masi
Affiliation:
Dipartimento di Chimica Fisica Applicata, Politecnico di Milano, Milano, ITALY
Sergio Carrá
Affiliation:
Dipartimento di Chimica Fisica Applicata, Politecnico di Milano, Milano, ITALY
Get access

Abstract

Palladium clusters have been chosen to represent a typical supported heterogeneous catalyst and their interaction with hydrocarbons has been investigated theoretically. The calculations were performed through density functional theory and the Becke-Lee-Yang-Parr hybrid (B3LYP) functional was adopted to calculate exchange and correlation energy. An effective core potential basis set (ECP on core electrons and Dunning/Huzinaga on outer electrons) was found sufficiently accurate to reproduce experimental data. Clusters containing up to seven Pd atoms were considered and their interaction with hydrogen, methane and ethane and their fragments was analyzed and a kinetic study of the system was performed. Transition states structures and energies were calculated through quantum mechanics and kinetic constants were derived from a statistic thermodynamic approach. On the basis of such information, a kinetic model that accounts for ethane transformations. Finally the kinetic scheme was embedded in a plug flow reactor model and simulations were performed to test the validity of the developed mechanism. In this way information obtained at the atomic scale were adopted to study phenomena occurring on the much higher reactor scale.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Satterfield, C. N., Heterogeneous Catalysis in Industrial Practice, 2nd ed. (McGrow-Hill: New York, 1991) pp. 201206.Google Scholar
2. Besenbacher, F., Chorkendorff, I., Clausen, B. S., Hammer, B., Molenbroek, A. M., Nørskov, J. K., and Stensgaard, I., Science 279, 1913 (1998).Google Scholar
3. Bertani, V., Cavallotti, C., Masi, M., and Carrà, S., J. Phys. Chem. A 104, 11390 (2000).Google Scholar
4. Becke, A. D., J. Chem. Phys. 98, 5648 (1993).Google Scholar
5. Lee, C., Yang, W., Parr, R. G., Phys. Rev. B 37, 785 (1988).Google Scholar
6. Hay, P. J., Wadt, W. R., J. Chem. Phys. 82, 270 (1985).Google Scholar
7. Wadt, W. R., Hay, P. J., J. Chem. Phys. 82, 284 (1985).Google Scholar
8. Hay, P. J., Wadt, W. R., J. Chem. Phys. 82, 299 (1985).Google Scholar
9. Dunning, T. H. Jr., Hay, P. J., in Modern Theoretical Chemistry, ed. Schaefer, H. F. III (Plenum: New York, 1976) pp. 128.Google Scholar
10. Frisch, M. J., Trucks, G. W., Schlegel, H. B., Scuseria, G. E. Robb, M. A., Cheeseman, J. R., Zakrzewski, V. G., Montgomery, J. A. Jr., Stratmann, R. E., Burant, J. C., Dapprich, S., Millam, J. M., Daniels, A. D., Kudin, K. N., Strain, M. C., Farkas, O., Tomasi, J., Barone, V., Cossi, M., Cammi, R., Mennucci, B., Pomelli, C., Adamo, C., Clifford, S., Ochterski, J., Petersson, G. A., Ayala, P. Y., Cui, Q., Morokuma, K., Malick, D. K., Rabuck, A. D., Raghavachari, K., Foresman, J. B., Cioslowski, J., Ortiz, J. V., Stefanov, B. B., Liu, G., Liashenko, A., Piskorz, P., Komaromi, I., Gomperts, R., Martin, R. L., Fox, D. J., Keith, T., Al-Laham, M. A., Peng, C. Y., Nanayakkara, A., Gonzalez, C., Challacombe, M., Gill, P. M. W., Johnson, B., Chen, W., Wong, M. W., Andres, J. L., Gonzalez, C., Head-Gordon, M., Replogle, E. S., Pople, J. A.; Gaussian 98, Revision A.6; Gaussian, Inc.; Pittsburgh, PA (1998).Google Scholar
11. Sinfelt, J. H., Kinetic Considerations in Surface Catalysis, Applied Kinetics and Chemical Reaction Engineering (ACS: Washington D. C., 1967) pp.1825.Google Scholar
12. Cimino, A., Boudart, M. and Taylor, H. S., J. Phys. Chem. 58, 796 (1954).Google Scholar
13. Karpinsky, Z., Adv. Catal. 37, 45 (1990).Google Scholar
14. Peng, C. and Schlegel, H. B., Israel J. Chem. 33, 449 (1993).Google Scholar
15. Christmann, K., Bull. Soc. Chim. Belge 88, 519 (1979)Google Scholar