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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Deng, ZY., Tanaka, Y., Sakka, Y. et al. Porous Al2O3/Al catalyst supports fabricated by an Al(OH)3/Al mixture and the effect of agglomerates. Journal of Materials Research 20, 672–679 (2005). https://doi.org/10.1557/JMR.2005.0077
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DOI: https://doi.org/10.1557/JMR.2005.0077