Study of electrolytic effect on the interaction between anionic surfactant and methylene blue using spectrophotometric and conductivity methods

The interaction studies of methylene blue (MB) as a cationic dye with an anionic surfactant were conducted. Conductometric and spectroscopic methods were used for investigations. The studies were performed at a wide range of SDS concentrations from pre to post micellar concentrations (1st and 2nd CMC of SDS). The large temperature range (275-313 K) was selected and thermodynamic parameters were evaluated. The dye recovery experiment was performed to observe the strength of interactions within the surfactants by using cetyltrimethylammonium bromide (CTAB) as a cationic surfactant. The role of salt effect using strong electrolytes was examined during the interaction. Interaction of surfactant with dye at 2nd CMC and the dimerization of MB in the presence of SDS were also witnessed.