SURFACE-ACIDITY AND CATALYTIC ACTIVITY OF ALUMINUM PILLARED MONTMORILLONITE

Aluminium pillared montmorillonite catalyst was prepared by interlayin g of Na-montmorillonite with aluminium hydroxy cations. Intercalation produces an expanded clay with increase in surface area and acidity. S pectroscopic studies with chemisorbed pyridine and ammonia have: shown that the interlayered clay contains both Lewis and Bronsted acid site s. The DSC thermograms of pyridine and ammonia adsorbed catalysts show the existence of three acidic sites with different strength on the su rface of the catalyst. Methanol dehydration to hydrocarbons, cracking of cumene and isopropylation of benzene on the aluminium pillared Mont morillonite have also been investigated and correlated to the acidity.