Acidity and temperature effect on the synthesis of SBA-1
Journal
Studies in Surface Science and Catalysis
Journal Volume
146
Pages
315-318
Date Issued
2002
Author(s)
Abstract
The formation of cubic phase SBA-1 is strongly influenced by the synthesis condition. In-situ XRD experiments showed that SBA-1 crystallized more quickly in higher acidic conditions, and no phase transformation was observed in the synthesis gel when varying either the reaction period or the acidity (HCl: TEOS molar ratio = 2∼5). Moreover, the cubic phase was less stable when the solid was separated from the mother liquid. A phase transformation from cubic to hexagonal was observed on the precipitates formed in short crystallization period when they were dried at room temperature. To the best of our knowledge, it was the first time in the literature to report that the phase transformation was correlated to the removing of the solvent from the precipitate. The stability of SBA-1 crystal structure was greatly improved by post-treatment of the wet products with ammonia solution. © 2003 Elsevier Science B.V. All rights reserved.
SDGs
Type
book