Phase Transition Activity Characteristics of Nanosized AlOOH in the Hydrothermal Synthesis of Nanosized α-Al₂O₃

Abstract:

α-Al2O3 nanopowders were prepared by a novel synthesis process, using the nanosized α-Al2O3 obtained from pyrolyzing ammonium aluminum carbonate hydroxide as seeds and the self-dispersed nanosized AlOOH crystal powders as precursors. Based on their good self-dispersion in water, the α-Al2O3 seeds were dispersed evenly into the AlOOH sol by the new homodispersion mixing technique. This process enables the conversion of AlOOH to alumina at 190°C (hydrothermal temperature), in which the alumina is calcined to nanosized alpha-alumina having an average length to diameter ratio of 60nm:15nm at 930°C. In the synthesis reaction for transforming the AlOOH to alumina, the effect of superfine pulverization and self-dispersion of the precursors was studied.

• Periodical: Key Engineering Materials (Volumes 368-372)
• Pages: 675-678
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.368-372.675
• Online since: February 2008
• Authors: Hai Da Liao, Lian Xiao Huang, Yan Bin Meng, Bo Lin Wu, Lian Meng Zhang
• Keywords: Boehmite, Crystal Seed, Hydrothermal Synthesis Method, α-Al₂O₃ Powder

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