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In Situ Electron Microscopy Studies of the Sintering of Palladium Nanoparticles on Alumina during Catalyst Regeneration Processes

Published online by Cambridge University Press:  22 January 2004

Rou-Jane Liu ,
Peter A. Crozier ,
C. Michael Smith ,
Dennis A. Hucul ,
John Blackson  and
Ghaleb Salaita
Rou-Jane Liu
Affiliation:
Center for Solid State Science, Arizona State University, Tempe, AZ 85287, USA
Peter A. Crozier
Affiliation:
Center for Solid State Science, Arizona State University, Tempe, AZ 85287, USA
C. Michael Smith
Affiliation:
Hydrocarbons and Energy R&D, Dow Chemical Company, Freeport, TX 77541, USA
Dennis A. Hucul
Affiliation:
Analytical Sciences Corporate R&D, Dow Chemical Company, Midland, MI 48667, USA
John Blackson
Affiliation:
Analytical Sciences Corporate R&D, Dow Chemical Company, Midland, MI 48667, USA
Ghaleb Salaita
Affiliation:
South Charleston Technical Center, Dow Chemical Company, South Charleston, WV 25303, USA
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Abstract

Sintering of a palladium catalyst supported on alumina (Al2O3) in an oxidizing environment was studied by in situ transmission electron microscopy (TEM). In the case of a fresh catalyst, sintering of Pd particles on an alumina surface in a 500 mTorr steam environment happened via traditional ripening or migration and coalescence mechanisms and was not significant unless heating above 500°C. After the catalyst was used for the hydrogenation of alkynes, TEM coupled with convergent beam electron diffraction and electron energy loss spectroscopy analysis revealed that most of the Pd particles were lifted from the alumina surface by hydrocarbon buildup. This dramatically different morphology totally changed the sintering mechanism of Pd particles during the regeneration process. Catalytic gasification of hydrocarbon around these particles in an oxidizing environment allowed the Pd particles to move around and coalesce with each other at temperatures as low as 350°C. For catalysts heating under 500 mTorr steam at 350°C, steam stripped hydrocarbon catalytically at the beginning, but the reaction stopped after 4 h. Heating in air resulted in both catalytic and noncatalytic stripping of hydrocarbon.

Keywords

in situ transmission electron microscopyPd catalystparticle sinteringoxidation environmentalumina supportcatalyst regeneration
Type
Research Article
Information
Microscopy and Microanalysis , Volume 10 , Issue 1 , February 2004 , pp. 77 - 85
Copyright
© 2004 Microscopy Society of America

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References

REFERENCES

Baker, R.T.K. (1989). Catalytic growth of carbon filaments. Carbon 27, 315–323.CrossRefGoogle Scholar
Baker, R.T.K. & Chludzinkski, J.J., Jr. (1986). In-situ electron microscopy studies of the behavior of supported ruthenium particles. 2. Carbon deposition from catalyzed decomposition of acetylene. J Phys Chem 90, 4734–4738.Google Scholar
Baker, R.T.K., Chludzinski, J.J., Dudash, N.S., Jr., & Simoens, A.J. (1983). The formation of filamentous carbon from decomposition of acetylene over vanadium and molybdenum. Carbon 21, 463–468.CrossRefGoogle Scholar
Baker, R.T.K., Prestridge, E.B., & McVicker, G.B. (1984). The interaction of palladium with alumina and titanium-oxide supports. J Catalysis 89, 422–432.CrossRefGoogle Scholar
Baker, R.T.K., Steveson, S.A., Dumesic, J.A., Raupp, G.B., & Tauster, S.J. (1987). Metal particle morphology and reducibility. In Metal-Support Interactions in Catalysis, Sintering, and Redispersion, Stevenson, S.C., Dumesic, J.A., Baker, R.T.A. & Ruckenstein, E. (Eds.), pp. 46–47. Boston: Van Nostrand Reinhold Company.
Chang, T.S., Rodriguez, N.M., & Baker, R.T.K. (1990). Carbon deposition on supported platinum particles. J Catalysis 123, 486–495.CrossRefGoogle Scholar
Chen, J.J. & Ruckenstein, E. (1981a). Sintering of palladium on alumina model catalyst in a hydrogen atmosphere. J Catalysis 69, 254–273.Google Scholar
Chen, J.J. & Ruckenstein, E. (1981b). Role of interfacial phenomenon in the behavior of alumina-supported palladium crystallites in oxygen. J Phys Chem 85, 1606–1612.Google Scholar
Crozier, P.A., Sharma, R., & Datye, A.K. (1998). Oxidation and reduction of small palladium particles on silica. Microsc Microanal 4, 278–285.CrossRefGoogle Scholar
Gai, P.L. (1983). Microstructural changes in vanadium pentoxide in controlled environments. Phil Mag 48, 359–371.CrossRefGoogle Scholar
Gai, P.L., Kourtakis, K., & Ziemecki, S. (2000). In situ real-time environmental high resolution electron microscopy of nanometer size novel xerogel catalysts for hydrogenation reactions in nylon 6,6. Microsc Microanal 6, 335–342.CrossRefGoogle Scholar
Gislason, J., Xia, W., & Sellers, H. (2002). Selective hydrogenation of acetylene in an ethylene rich flow: Results of kinetic simulations. J Phys Chem A 106, 767–774.CrossRefGoogle Scholar
Hansen, T.W., Wagner, J.B., Hansen, P.L., Dahl, S., Topsoe, H., & Jacobsen, C.J.H. (2001). Atomic-resolution in situ transmission electron microscopy of a promoter of a heterogeneous catalyst. Science 294, 1508–1510.CrossRefGoogle Scholar
Hansen, P.L., Wagner, J.B., Helveg, S., Rostrup-Nielsen, J.R., Clausen, B.S., & Topsoe, H. (2002). Atomic-resolved imaging of dynamic shape changes in supported copper nanoparticles. Science 295, 2053–2055.CrossRefGoogle Scholar
Lin, T.B. & Chou, T.C. (1995). Pd migration. 1. A possible reason for the deactivation of pyrolysis gasoline partial hydrogenation catalysts. Ind Eng Chem Res 34, 128–134.Google Scholar
Owens, W.T., Rodriguez, N.M., & Baker, R.T.K. (1992). Carbon filament growth on platinum catalysts. J Phys Chem 96, 5048–5053.CrossRefGoogle Scholar
Rodriguez, N.M., Oh, S.G., Dalla-Betta, R.A., & Baker, R.T.K. (1995). In situ electron microscopy studies of palladium supported on Al2O3, SiO2 and ZrO2 in oxygen. J Catalysis 157, 676–686.CrossRefGoogle Scholar
Ruckenstein, E. (1987a). Introduction to the role of interactions and surface phenomena in sintering and redispersion of supported metal catalysts. In Metal-Support Interactions in Catalysis, Sintering, and Redispersion, Stevenson, S.C., Dumesic, J.A., Baker, R.T.A. & Ruckenstein, E. (Eds.), pp. 141–155. Boston: Van Nostrand Reinhold Company.
Ruckenstein, E. (1987b). Wetting and spreading. In Metal-Support Interactions in Catalysis, Sintering, and Redispersion, Stevenson, S.C., Dumesic, J.A., Baker, R.T.A. & Ruckenstein, E. (Eds.), pp. 230–233. Boston: Van Nostrand Reinhold Company.
Sarkany, A., Weiss, A.H., Szilagyi, T., Sandor, P., & Guczi, L. (1984). Green oil poisoning of a Pd/Al2O3 acetylene hydrogenation catalyst. Appl Catalysis 12, 373–379.CrossRefGoogle Scholar
Sharma, R. & Weiss, K. (1998). Development of a TEM to study in situ structural and chemical changes at atomic level during gas solid interaction at elevated temperature. Microsc Res Tech 42, 270–280.3.0.CO;2-U>CrossRefGoogle Scholar