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Porous Al2O3/Al catalyst supports fabricated by an Al(OH)3/Al mixture and the effect of agglomerates

Published online by Cambridge University Press:  01 March 2005

Zhen-Yan Deng*
Affiliation:
Composite Materials Group, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan
Yoshihisa Tanaka
Affiliation:
Composite Materials Group, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan
Yoshio Sakka
Affiliation:
Fine Particle Processing Group, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan
Yutaka Kagawa
Affiliation:
Composite Materials Group, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan; and Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
*
a)Address all correspondence to this author. e-mail: DENG.Zhenyan@nims.go.jp
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Abstract

Porous Al2O3/Al catalyst supports were fabricated using a mixture of Al(OH)3 and Al powders, followed by pressureless sintering at a temperature of 600 °C in vacuum. Different pressures were used to prepare green compacts. High compaction pressure led to a high surface area and good mechanical and electrical properties for the sintered specimens. However, when the Al content in the sintered specimen exceeded a definite value, high compaction pressure decreased the surface area abruptly. Scanning electron microscopy observations revealed that agglomeration in the starting mixture has a significant effect on the microstructure of the sintered specimens. High compaction pressure greatly eliminated the agglomerates and led to a uniform microstructure for the sintered specimens. However, when the Al content in the starting mixture was too high, Al particles in the compacts prepared by the high pressure were largely sintered due to the high compact density so that most of the pores were closed. The present study indicates that a suitable compaction pressure is critical to obtaining superior Al2O3/Al supports.

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Articles
Copyright
Copyright © Materials Research Society 2005

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