Molecular Interaction in Ternary Systems of Tri-n-octylamine/Tri-n-butyl Phosphate/Octanoic Acid with n-Hexane and 1-Hexanol at Different Temperatures

Density, dielectric constant and refractive index were measured for three ternary systems viz. tri-n-octylamine/tri-n-butyl phosphate/octanoic acid (TOA/TBP/OA), with n-hexane and 1-hexanol at T = 303.15, 308.15 and 313.15 K. Derived properties like molar volume, molar polarization, molar refraction and excess parameters were calculated from the measured density, dielectric constant and refractive index values, respectively. The excess values were also calculated with the Redlich-Kister polynomial and the fitting coefficients and standard deviations are reported. The density of the ternary mixtures increased with the increase in the mole fraction of the solute and decreased with the rise of temperature. The negative dielectric constant values for all the systems indicate a reduction in effective dipoles due to the dipolar self-association of the polar molecules. The FT-IR spectra of all the systems indicate a feeble interaction among the extractants, diluent and modifier.