Thermodynamic Study of the Interaction Between C.I. Reactive Red180 with Cationic Gemini Surfactant in Aqueous Solution

Abstract

Interactions between Reactive Red 180 and cationic gemini surfactant solutions were investigated by means of electrical conductivity measurements at different temperatures ranging from 298.15 to 323.15 K. Gemini surfactant of the type N,N'-didecyl-N,N,N',N'-tetramethyl-N,N'-ethanediyldiammonium dibromide referred as (10-2-10) was synthesized in our laboratory. It was observed that a decrease in the measured specific conductance of dye-gemini surfactant mixtures was caused by the formation of nonconducting or less conducting dye-surfactant associates. The aggregation of surfactant and dye takes place at a surfactant concentration far below the critical micelle concentration of the individual surfactant. The long-range electrostatic forces and short-range hydrophobic interactions are very important factors at the dye-surfactant aggregation in aqueous solutions. From conductivity data for dyes-gemini surfactant interaction such as micellar ionization degree, counterion binding, equilibrium constant and thermodynamic parameters of interaction were calculated. Thermodynamic parameters of interaction indicate that interaction of dye-(10-2-10) is enthalpy driven.