NEW ROUTES TO THE PREPARATION OF PILLARED MONTMORILLONITE CATALYSTS

Clay catalysts have been prepared using reagents different from the aluminum chlorhydrate solution usually employed to pillar smectite minerals. Colloidal alumina, alumina-coated silica and solutions containing chlorhydrated complexes of zirconium and aluminum produced pillared bentonites which, upon calcination at 400 degree C, formed microporous two-dimensional structures with 200-500 m**2 g** minus **1 Langmuir surface area and basal spacing between 17 and 18 Angstrom. These pillared clays contain both Bronsted and Lewis acid sites; above 300 degree C, pyridine is retained predominantly on Lewis centers.