PILLARING OF SAPONITE WITH ZIRCONIUM OLIGOMERS

The intercalation of two saponites and a montmorillonite with various zirconium oligomers, prepared from the hydrolysis of zirconyl chloride or zirconium acetate, has been studied. The structure of the intercal ated clays strongly depended on the method of preparation and on the n ature and crystallinity of the clays studied. In some cases, well-orde red intercalated clays (with basal spacings between 18 and 20 Angstrom ) were obtained, while in other cases noncrystalline solids were obtai ned. Delamination and/or an acid activation of the clays seem to take place when the intercalation suspensions obtained from zirconyl chlori de are subjected to a reflux treatment. The specific total surface are a and specific micropore volume of the solids reached values up to 300 m(2) g(-1) and 0.120 cm(3) g(-1), respectively. The amount of ZrO2 fi xed varied between 10 and 28% of the weight of the intercalated sample s. In general, best results were obtained when using zirconium acetate as precursor, instead of zirconyl chloride. (C) 1998 Elsevier Science B.V. All rights reserved.