Purification of corundum by calcination under controlled reducing conditions

Authors
Souto, A Rodriguez, A Guitian, F
Citation
A. Souto et al., Purification of corundum by calcination under controlled reducing conditions, J EUR CERAM, 20(6), 2000, pp. 695-698
Citations number
9
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
ISSN journal
09552219 → ACNP
Volume
20
Issue
6
Year of publication
2000
Pages
695 - 698
Database
ISI
SICI code
0955-2219(200005)20:6<695:POCBCU>2.0.ZU;2-K
Abstract
The alkaline impurities detract from the mechanical properties of corundum materials, specially at high temperatures. So it is important that they are minimized. This paper describes a new purification method of aluminas by c alcination at high temperatures (>1200 degrees C) in controlled reducing at mospheres (P(o2)similar to 10(-15) atm). Under these conditions, alkaline i mpurities are removed by reduction to volatile species. Over 95% of Na2O ex isting in the alumina can be removed in this way. SiO2 and Fe2O3 can also b e removed with these treatments. (C) 2000 Elsevier Science Ltd. All rights reserved.