Viscosity and density of ternary mixture of di-(2-ethylhexyl)phosphoric acid (DEHPA)-benzene-toluene

Viscosities and densities of the ternary liquid mixtures of di (2-ethylhexy l) phosphoric acid + benzene + toluene have been measured at 30, 35, 40 and 45 degrees C. The mixture viscosity, eta(m), is fitted to a Redlich-Kister -type equation which includes the contribution of each constituent binary s ystem along with a ternary contribution term. The non-idealities reflected in mixture viscosities are expressed and discussed in terms of excess visco sities which are negative over the entire range of mole fraction. Negative values of excess viscosity, eta(E), and the nonlinear variation of viscosit y and density with change of composition indicate molecular interaction bet ween the polar extractant and non-polar diluents.