Thermal stability of montmorillonite intercalated and alumina pillared by Boehmite Sol

Abstract

Mono ion exchanged montmorillonite has been intercalated with monohydroxy aluminium oxide (Boehmite, AlOOH) by refluxing a mixture of the montmorillonite and boehmite in an aqueous medium. The alumina pillared montmorillonite has been prepared by further dehydroxylation of the intercalated material. Characteristics of the pillared smectite with respect to specific surface area, interlayer spacing and extent of pillaring by chemical estimation of alumina content is described. The thermal decomposition characteristics of the boehmite on intercalation with sodium and cerium exchanged montmorillonite shows distinct difference from the corresponding thermal analysis curves. The cerium exchanged montmorillonite shows a specific surface area of 300 m 2/g and 190 m 2/g on heating to 300°C and 800°C, respectively, while the one exchanged with sodium had 213 m 2/g and 92 m 2/g. The present work highlights the significance of following thermal analysis curves of intercalated montmorillonites in deciding the temperature of dehydroxylation to pillare intercalated smecite (PILC) as applied to boehmite as intercalent on sodium and cerium exchanged montmorillonite.