THE INTERCALATION OF 2,2'-BIPYRIDINE AND 1,10-PHENANTHROLINE AND THEIR COMPLEXES WITH IRON WITHIN THE INTERLAYER REGIONS OF MONTMORILLONITE CLAY

The intercalation of 2,2'-bipyridine and 1,10-phenanthroline and their complexes with iron within the interlayer regions of montmorillonite clay has been examined by a range of techniques. The intercalation of 2,2'-bipyridine within different size fractions of natural- and sodium-exchanged montmorillonite has been shown by X-ray diffraction to increase the interlayer spacings. Infrared spectroscopy indicates that some of the intercalated 2,2'-bipyridine undergoes complex formation with Fe2+ located at the surface structure of the interlayer region. The intercalation into montmorillonite of Fe(bipy)3(2+) and Fe(phen)3(2+) complexes from solution has been monitored by recording the visible absorbance spectra of the supernatant liquids withdrawn from the preparation media. The extent of intercalation has been correlated with the cation exchange capacity of the clay and the different behaviour of the two complexes is associated with their diffusion into the interlayer regions of the montmorillonite clay.