Adsorption of dyes on a silica surface

Adsorption of several organic dyes was examined on a modified silica surface. For this purpose, EG-Silica was applied, precipitated from sodium metasilicate solution using carbon dioxide in presence of ethylene glycol. In order to promote their interaction with dyes, the silica surface was modified using silane coupling agents with the amino functional group. Technique of conducting the adsorption process was discussed. Studies on morphology and microstructure were performed employing scanning electron microscopy (SEM). Particle size distribution was also examined using the technique of dynamic light scattering. The SEM micrographs and particle size distributions showed that highly uniform pigments can be obtained employing EG-Silica as a core. Studies on elution of dyes from the silica surface demonstrated that, in general, stable pigments were obtained.