The Malaysian Journal of Analytical Sciences Vol 11 No 1 (2007): 110 – 116

 

 

EFFECT OF TEMPLATES ON THE SYNTHESIS OF ORGANIZED MESOPOROUS ALUMINA

 

Zainab Ramli and Sheela Chandren

 

Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia,

81310 Skudai, Johor.

 

Abstract

Organized mesoporous materials represent a class of molecular sieves because of its high potential for  commercial applications in adsorption and catalysis . In this study, organized mesoporous alumina was synthesized by the sol-gel method using various organic templates, i.e. cationic, neutral and anionic surfactants. Surface porosity of t he synthesized aluminas obtained exhibit materials in the mesopore ranges . The morphology of the samples consists of wormhole-like mesostructure in the nano-region (20 – 70 nm). Sample with cetyl trimethylammonium bromide as cationic templates has the narrowest pore distribution centred at 8 nm as compared to samples synthesized with Triton X-114 (neutral) and stearic acid (anionic). All samples showed only Lewis acidity. Acidity and mesoporous character present in these mesoporous alumina samples showed that this material has potential as catalyst support and also used in Lewis acid catalyzed reactions. Study showed that the cationic  surfactant is a better  template to obtain uniform mesoporous alumina that might  be due to the weak interaction between the template and the surface of the alumina.

 

Keywords : Mesoporous alumina, templates, catalyst

 

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