Al and Zr pillared acid-activated saponite clays: characterization and properties

Abstract

An acid-activated saponite has been used in the preparation of Al and Zr pillared acid-activated clays. The properties of this new family of pillared clays (pillared acid-activated saponites, PAASs) have been compared to those of conventional pillared (non-activated) saponites (PILSs). It is found that the acid treated materials incorporate less Al or Zr than the parent saponite, with the most likely cause being the reduced cation exchange capacity of the matrix following acid-activation. Powder X-ray diffraction suggests that Al PAASs are thermally more stable than the corresponding Zr PAASs. The acidity of the pillared materials (as monitored by cyclohexylamine adsorption–desorption thermogravimetry studies) is related to the nature and to the amount of the metal oxides incorporated between the sheets of the host clays. Catalytic data for the Brønsted catalysed dehydration ofpentan-1-ol is reported.