THE INTERCALATION OF CSF IN KAOLINITE

Caesium aluminium silicates, caesium aluminium fluoride and aluminium fluoride were identified in a mixture obtained through the evaporation of kaolinite aqueous suspension with CsF. The mixture was studied by X-ray powder diffraction and IR spectroscopy. Two types of intercalati on complexes of kaolinite were identified (A and B) which were charact erized by c-spacings of similar to 0.99 and 0.83 nm, respectively. Com plex A seems to be an hydrated CsF intercalation complex, whereas comp lex B is a water intercalation complex, probably containing H3O degree s and F-. It showed an IR absorption band at 3518 cm(-1). The c-spacin gs of similar CsCl and CsBr complexes depend on the ionic radii. The i ntercalated ions are keyed into the ditrigonal cavities of the oxygen plane. A straight line plot of the keying values versus the ionic size indicates that keying is high for F-and decreases with increasing ion ic size.