CATIONIC MIXED PILLARED LAYER CLAYS - INFRARED AND MOSSBAUER CHARACTERISTICS OF THE PILLARING AGENTS AND PILLARED STRUCTURES IN FE,AL AND CR,AL PILLARED MONTMORILLONITES

摘要

Pillared layer clays containing Fe,Al or Cr,Al mixed pillars were synthesized and characterized with mid and far FT-IR and Fe-57 Mossbauer spectroscopies. Spectra of the pillaring ions and the pillared materials indicated that co-hydrolysis and co-pillaring occurred. Isomorphous substitution of either tetrahedral or octahedral Al in the Al-13-Keggin ion did not take place. The layers of montmorillonite were propped apart by a mixture of [AlO4Al12(OH)(24)(H2O)(12)](7+) Keggin ions and hydrous iron oxide or hydrous chromium oxide, alternately. (C) 1997 Elsevier Science B.V. [References: 14]