Non-aggressive pillaring of clays with zirconium acetate. Comparison with alumina pillared clays

A non-aggressive method of intercalation of smectitic clays with zirconium oligomers from the hydrolysis of a commercial solution of zirconium acetate is presented. Two saponites and a montmorillonite have been selected as th e starting materials. The conditions of the intercalation process, pH=3.3 a nd room temperature, seem to allow a high polymerization degree of the inte rcalation zirconium species without significantly affecting the layer clay structures. Basal spacings in the 14-24 Angstrom range are obtained for the zirconia pillared clays after thermal treatment at 500 degrees C. Moreover , the specific surface areas and specific micropore volumes of the zirconia pillared clays reached values up to 300 m(2)/g and 0.140 cm(3)/g, respecti vely. The amounts of ZrO2 fixed varied between 27% and 36% of the weight of the pillared samples. The textural properties of the zirconium intercalate d clays were compared with that of their aluminum intercalated counterparts , resulting in higher specific surface areas and micropore volumes for the zirconia pillared saponites calcined at 500 degrees C. (C) 1999 Elsevier Sc ience B.V. All rights reserved.