Solubilization of reactive dyes by mixed micellar system: Synergistic effect of nonionic surfactant on solubilizing power of cationic surfactant

Abstract

In this manuscript solubilization of reactive dyes i.e. Reactive red 195 and reactive blue 221, by simple and mixed micellar solution, is being reported using UV/visible spectroscopy and electrical conductivity. UV/visible spectroscopy has been used to have quantitative measurement of degree of solubilization in term of partition coefficient (Kx) and Gibbs energy of partition (ΔGp) while electrical conductivity has been employed to detect critical micelle concentration of surfactants and, accordingly, to calculate thermodynamic parameters. It has been concluded that solubilization is exothermic, spontaneous and enthalpy driven process. The partitioning and binding of RB-195 has been found to be more favorable and spontaneous than that of RB-221. The results clearly indicate that the inclusion of TX-100 in micellar media of CTAB has significantly enhanced its solubilizing power.