Hostname: page-component-848d4c4894-5nwft Total loading time: 0 Render date: 2024-05-22T18:23:38.960Z Has data issue: false hasContentIssue false
  • English
  • Français

On the morphological properties of tungsta-titania de-NOxing catalysts

Published online by Cambridge University Press:  31 January 2011

C. Cristiani ,
M. Bellotto ,
P. Forzatti  and
F. Bregani
C. Cristiani
Affiliation:
Dipartimento di Chimica Industriale e Ingegneria Chimica del Politecnico, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy
M. Bellotto
Affiliation:
CISE, P.O. Box 12081, 20134 Milano, Italy
P. Forzatti
Affiliation:
Dipartimento di Chimica Industriale e Ingegneria Chimica del Politecnico, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy
F. Bregani
Affiliation:
ENEL-CRTN, Via Monfalcone 15, 20100 Milano, Italy
Get access

Abstract

Tungsta-titania samples with different W loadings up to 15 wt.% and calcined at different temperatures have been prepared and characterized by surface area measurements, mercury porosimetry, x-ray diffraction, microstructural analysis, and laser Raman spectroscopy. It has been found that W inhibits the initial sintering of TiO2 (anatase) and the anatase → rutile transformation. The morphological and structural properties of the samples (surface area, porosity, and phase composition) have been related to the microscopic properties of the materials such as crystallite dimensions and defects concentration. A model for the sintering of TiO2 is discussed. This model is based on the diffusion of surface hydroxyls, formed upon adsorption of water on surface oxygen vacancies. A role for W is proposed in terms of stabilization of both material defects and surface hydroxyls.

Type
Articles
Information
Journal of Materials Research , Volume 8 , Issue 8 , August 1993 , pp. 2019 - 2025
Copyright
Copyright © Materials Research Society 1993

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

1Bosch, H. and Janssen, F., Catal. Today 2, 369 (1988).CrossRefGoogle Scholar
2EPA/EPRI Joint Symposium on Stationary Combustion NOx Control, Washington, DC, March 25-28 (1991).Google Scholar
3Beckman, J.W. and Hegedus, L.L., I&EC Res.(1991, in press); E. Tronconi, A. Beretta, P. Forzatti, S. Malloggi, and G. DeMichele, in Tecnologie Chimiche per la Produzione di Energia Elettrica, Pisa, October 29–31 (1991), p. 417.Google Scholar
4Inomata, M., Mori, K., Miyamoto, A., Ui, T., and Murakami, Y., J. Phys. Chem. 87, 754 (1983).CrossRefGoogle Scholar
5Solid State Chemistry in Catalysis, edited by Andersson, A., Andersson, S. L. T., Grasselli, R. K., and Bradzil, J. F. (American Chemical Society, Washington, DC, 1985, p. 121.CrossRefGoogle Scholar
6Gellings, P. J., Catalysis (The Royal Society of Chemistry, London, 1985, vol. 7, p. 105.Google Scholar
7Haber, J., Kozlowska, A., and Kozlowski, R., J. Catal. 102, 52 (1986).CrossRefGoogle Scholar
8Vejoux, A. and Courtine, P., J. Solid State Chem. 63, 179 (1986).Google Scholar
9Busca, G., Tittarelli, P., Forzatti, P., and Tronconi, E., J. Solid State Chem. 67, 91 (1987).Google Scholar
10Cavani, F., Foresti, E., Parrinello, G., and Trifiro, F., Appl. Catal. 38, 311 (1988).CrossRefGoogle Scholar
11Hausinger, G., Schmelz, H., and Knozinger, H., Appl. Catal. 38, 267 (1988).CrossRefGoogle Scholar
12Bond, G. C., Flamerz, S., and Shukri, R., Faraday Discussion Chem. Soc. 87, 65 (1989).CrossRefGoogle Scholar
13Eckert, H. and Wachs, I. E., J. Phys. Chem. 93, 6796 (1989).CrossRefGoogle Scholar
14Wenl, G. T., Oyama, S. T., and Bell, A. T., J. Phys. Chem. 94, 4240 (1990).Google Scholar
15Bond, G. C., Flamerz, S., and Wijk, L. van, Catal. Today 1, 229 (1987).CrossRefGoogle Scholar
16Vermair, D. C. and Berge, P. C. van, J. Catal. 116, 309 (1989).Google Scholar
17Ramis, G., Busca, G., Cristiani, C., Lietti, L., Forzatti, P., and Bregani, F.Langmuir 8, 1744 (1992).CrossRefGoogle Scholar
18Spurr, R.A. and Myers, H., Anal. Chem. 31, 2481 (1978).Google Scholar
19Mignot, J. and Rondot, D., Acta Crystallogr. A 33, 327 (1977).Google Scholar
20Boni, C., Caruso, E., Cereda, E., Marcazzan, G. M. Braga, and Redaelli, P., Nucl. Instrum. Methods in Phys. Res. B 40/41, 620 (1989).Google Scholar
21Hosemann, R. and Bagchi, S.N., in Direct Analysis of Diffraction by Matter (North-Holland Publishing Co., Amsterdam, 1962).Google Scholar
22Fischer, A., Hosemann, R., Vogel, W., Koutecky, J., Pohl, J., and Ralek, M., New Horizons in Catalysis, Proc. 7th Int. Congress on Catalysis, Tokyo, June 30-July 4 (1980), pp. 341–354.Google Scholar
23Ludwiczek, H., Preisinger, A., Fischer, A., Hosemann, R., Schonfeld, A., and Vogel, W., J. Catal. 51, 326 (1978).CrossRefGoogle Scholar
24Wang, J. C., Metall. Trans. 21A, 305 (1990).CrossRefGoogle Scholar
25Anderson, P. J. and Morgan, P. L., Trans. Faraday Society 60, 930 (1964).CrossRefGoogle Scholar
26Eastman, P.F. and Cutler, I.B., J. Am. Ceram. Soc. 49, 526 (1966).CrossRefGoogle Scholar
27German, R. M. and Munir, Z. A., J. Am. Ceram. Soc. 59, 379 (1976).Google Scholar
28Varela, J.A. and Whittemore, O.J., J. Am. Ceram. Soc. 66, 77 (1983).Google Scholar
29Beruto, D., Botter, R., and Searcy, A.W., J. Am. Ceram. Soc. 70, 155 (1987).CrossRefGoogle Scholar
30Hebrard, J.L., Nortier, P., Pijolat, M., and Soustelle, M., J. Am. Ceram. Soc. 73, 79 (1990).CrossRefGoogle Scholar
31Cristiani, C., Busca, G., and Forzatti, P., J. Catal. 116, 586 (1989).CrossRefGoogle Scholar
32Ramis, G., Cristiani, C., Forzatti, P., and Busca, G., J. Catal. 124, 574 (1990).CrossRefGoogle Scholar
33and, R.D. ShannonPask, J.A., J. Am. Ceram. Soc. 48, 391 (1965).Google Scholar
34Shannon, R.D. and Pask, J.A., Am. Mineral. 49, 1707 (1964).Google Scholar
35Criado, J.M., Real, C., and Soria, J., Solid State Ionics 32/33, 461 (1989).CrossRefGoogle Scholar