Influence of a Crown Ether on the Spectral Properties of Triarylmethane Dyes in Aqueous and Micellar Environments

This study demonstrates the spectral data for two triarylmethane dyes, malachite green and crystal violet, at room temperature. Effects of micellar environment and crown ether addition on the spectral behaviour of these dyes are studied using absorption spectroscopic method. The dye-anionic surfactant interactions in micellar media are investigated. The chosen surfactants with different alkyl chain length are SOS, STS, SHS and SDS. Effect of a crown-ether (i.e. aza-15-crown-5) addition on the absorption spectra and decolorization of the dyes is also studied at room temperature. Moreover, effect of crown ether addition on the micellar properties of the media is studied and compared. Spectroscopic analysis shows that the dye decolorization can be accelerated in presence of the crown ether. Conversely, the decolorization process can be inhibited in the micellar media. The nature of decolorization process is interpreted in terms of direct and indirect mechanisms of crown-ether and the dye interactions.