PREPARATION AND CHARACTERIZATION OF PILLARED GALLIUM ALUMINUM CLAYS WITH ENRICHED PILLARS

Bentolite-H pillared with GaO4Al12(OH)(24)(H2O)(12)(7+) (GaAl12/B-H) i s thermally stable above 700 degrees C. The cation exchange capacity ( CEC) of GaAl12 pillared clay is restored by heat treatment in an ammon ia atmosphere. This pillared clay is then reintercalated with Ga-13, G aAl12, and Al-13 polyoxycations. XRD, surface area, and pore size meas urement data show that additional pillars are introduced into the pill ared clay. The data for thermal stability of repillared samples indica te improvements in desired properties after reintercalation, especiall y for GaAl12 repillared material. Acidic studies show that the additio nal pillars introduced by repillaring produce more acid sites on pilla red clays. Both Bronsted and Lewis sites are detected on three repilla red clays.