Silica-Supported Magnetite Shift Catalysts
Silica-supported magnetite shift catalysts were the subject of Carl's Ph. D. studies at the University of Wisconsin, Madison (Go Badgers!). This work was conducted under the supervision and with the guidance of Jim Dumesic. At the time (late 70's - early 80's), the catalysis community was way ahead of the nanotechnology revolution. It was well established that the activity of some metal catalysts changed markedly when the size of the particles became smaller than ca. 5 nm. The original objective of Carl's project was to investigate whether this kind of structure sensitivity was observed for iron oxide water-gas shift catalysts.
It turned out that when very small particles of magnetite were supported on silica, there was a strong interaction between the two oxides. As a consequence of this strong oxide-oxide interaction, the shift activity decreased considerably. Thus, project focus shifted to understanding the origins of the activity decrease. The evidence suggested that silicon cations enter the magnetite particles, and this strongly affects the ease of ferrous - ferric cation redox processes. In addition to characterization studies, the project also included studies to develop a method for titrating the iron oxide surface area of the supported catalysts.
Papers Resulting from this Project
“Strong Oxide-Oxide Interactions in Silica-Supported Magnetite Catalysts: IV. Catalytic Consequences of the Interaction in Water-Gas Shift,” Carl R. F. Lund and James A. Dumesic, J. Catal. 76, 93 (1982). [more info]
“Strong Oxide-Oxide Interactions in Silica-Supported Magnetite Catalysts: II. The Core/Shell Nature of the Interaction,” Carl R. F. Lund and James A. Dumesic, J. Phys. Chem. 86, 130 (1982). [more info]
“Strong Oxide-Oxide Interactions in Silica-Supported Magnetite Catalysts: III. Water-Induced Migration of Silica on Geometrically Designed Catalysts,” Carl R. F. Lund and James A. Dumesic, J. Catal. 72, 21 (1981). [more info]
“Strong Oxide-Oxide Interactions in Silica-Supported Magnetite Catalysts: I. X-ray Diffraction and Mössbauer Spectroscopy Evidence for Interaction,” Carl R. F. Lund and James A. Dumesic, J. Phys. Chem. 85, 3175 (1981). [more info]
“Magnetite Surface Area Titration Using Nitric Oxide, II. Pretreatment Effects and Silica-Supported Samples,” Joseph E. Kubsh, Carl R. F. Lund and James A. Dumesic, React. Kinet. Catal. Lett. 17, 115 (1981). [more info]
“Magnetite Surface Area Titration Using Nitric Oxide,” Carl R. F. Lund, James J. Schorfheide and James A. Dumesic, J. Catal. 57, 105 (1979). [more info]
Conference Proceedings Resulting from this Project
“Water-Gas Shift Over Magnetite-Based Catalysts: Nature of Active Sites for Adsorption and Catalysis,” C. R. F. Lund, J. E. Kubsh and J. A. Dumesic, ACS Symposium Series, “The Role of Solid State Chemistry in Catalysis” 279, 313 (1985). [more info]
Presentations Resulting from this Project
“Water Gas Shift Reaction over Magnetite Catalyst,” AIChE 1990 Spring National Meeting, Orlando, March 19, 1990.
“Active Sites on Magnetite Water-Gas Shift Catalysts,” ACS Meeting, Miami Beach, 1985.
“Strong Oxide-Oxide Interactions in Fe3O4/SiO2 Water-Gas Shift Catalysts,” North American Catalysis Society Meeting, Boston, 1981.
“Structure Sensitivity in Reactions on Oxides: The Water-Gas Shift over Fe3O4,” Annual AIChE Meeting, Chicago, 1980.
“Supported Magnetite Catalysts for the Water-Gas Shift: Surface Titration using Nitric Oxide,” Annual AIChE Meeting, Miami, 1978.
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