title: The rhodamine B intercalation of montmorillonite.
abstract: Using photometric methods the dissociation constants and weight fractions of rhodamine B dimer in water solutions at different concentrations were determined. The montmorillonite (SWy) samples were fully intercalated with rhodamine B (RhB) solutions at various monomer/dimer ratios. The amount of rhodamine B in fully intercalated montmorillonite (RhB-SWy) increases with increasing concentration of dye in water solutions, i.e., with increasing dimer/monomer ratio. The sum of exchangeable guest cations in RhB-SWy is approximately constant (0.900 meq g(-1)) for all samples, because RhB-SWy samples with prevailing dye monomer also contain higher amounts of non-exchanged alkali elements. The experimental data are supported by calculated structure models that illustrate the changes in RhB-SWy structure depending on monomeric and/or dimeric arrangement of guests. The analysis of the calculated structure models confirmed the existence of two phases with different basal spacings, d approximately 1.8 and approximately 2.3 nm, revealed by X-ray diffraction.
authors.affiliation: VSB-Technical University Ostrava, 708 33 Ostrava-Poruba, Czech Republic. zdenek.klika@vsb.cz
authors.forename: Z
authors.initials: Z
authors.lastname: Klika
authors.forename: H
authors.initials: H
authors.lastname: Weissmannová
authors.forename: P
authors.initials: P
authors.lastname: Capková
authors.forename: M
authors.initials: M
authors.lastname: Pospísil