Efficient Preparation of Submicrometer α-Alumina Powders by Calcining Carbon-Covered Alumina
Abstract:A simple method is described to prepare submicrometer α-alumina by burning carbon supported on the surface of -alumina in oxygen flow at a temperature of 800°C. The burning of carbon generates a large amount of heat and leads to a rapid increase in the local temperature inside the pores of alumina. When the temperature is high enough for the phase transformation, α-alumina is obtained in a very short time. It was found that, for carbon contents between 6 and 10 wt%, all the -alumina could transform into α-alumina after burning of carbon in oxygen for a short time, and the transformed particle sizes of α-alumina were mostly no more than 1 m.
Document Type: Research Article
Affiliations: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, 100871 Beijing, China
Publication date: 2006-09-01