Silica Gel Dyeing by Adsorption of a Series of Triphenylmethane Dyes on its Surface

In this work, both the binding constants (K) of some triphenylmethane dyes on the silica gel surface and its dyeing and the effect of temperature on K values were studied by the ARIAN model. These dyes included malachite green (MG), fuchsine acid (FA), methyl green (MEG), brilliant green (BG) and crystal violet (CV) and the dyeing process was carried out in aqueous media at 308, 318 and 328 K. The results showed that in all cases the process was two-region and endothermic. Here, the role of amine and functional groups of dyes in their interactions with silica gel surface was discussed. Maximum adsorption capacities of silica gel for MG, FA, MEG, BG, and CV dyes were 4.2, 5.4, 5.9, 6.9 and 7.5 mg g-1 at 328 K, respectively.