SPECTROSCOPIC STUDY OF THE ADSORPTION OF RHODAMINE 6G ON CLAY-MINERALS IN AQUEOUS SUSPENSIONS

Absorption and fluorescence spectroscopies were applied to study the a dsorption of rhodamine 6G on several smectite-type clays in aqueous su spension. The dye can be adsorbed as the monomeric and the dimeric for ms on both the external and the interlamellar surfaces of the clay. Th e presence of these species and their evolution with the stirring time of the sample and the relative dye/clay concentration depend on the n ature of the smectite, the clay concentration and the particle size, f actors that also affect the dispersion degree of the clay particles in water.