Zeolite NaY nanocrystals (20-50 nm) were hydrothermally grown on polyelectrolyte-coated three-dimensionally ordered macroporous (3DOM) activated zirconia. The zeolite nanocrystallites uniformly coated the macropore walls of 3DOM sulfated zirconia, but sulfate groups were lost during the hydrothermal reaction. 3DOM tungstated zirconia was found to be more stable in the strong basic environment of the zeolite precursor solution. Further, ion-exchange of zeolite NaY with ruthenium followed by hydrogen-reduction formed a composite of RuNaY and 3DOM activated zirconia. The presence of ruthenium was confirmed by X-ray photoelectron spectroscopy and the external shape of zeolite nanoparticles was maintained after ion-exchange, but the zeolite lattice fringes could not be observed by transmission electron microscopy after incorporation of reduced ruthenium. Although the catalytic activity of the materials has not yet been tested, these hierarchical nano- and microstructures bring multiple catalyst components (modified zeolite Y, a typical Fischer-Tropsch catalyst, and activated zirconia, an isomerization catalyst) together in intimate contact for potential multi-reaction processes.
Bibliographical noteFunding Information:
This research was supported by the Petroleum Research Foundation administered by the American Chemical Society (ACS-PRF Grant Number 42751-AC10) and the Office of Naval Research (Grant Number N00014-07-1-00608). Parts of this work were carried out in the Institute of Technology Characterization Facility, University of Minnesota, which receives partial support from the NSF through the NNIN and MRSEC programs. Z.W. thanks the University of Minnesota Graduate School for a Doctoral Dissertation Fellowship.
Copyright 2009 Elsevier B.V., All rights reserved.
- Colloidal crystal templating
- Sulfated zirconia
- Tungstated zirconia
- Zeolite RuNaY nanocrystals