Effect of polarity and temperature on the binary interaction between D2EHPA extractant and organic solvents (kerosene, n-heptane, chlorobenzene and 1-octanol): Experimental and thermodynamics

The density and viscosity of binary mixtures of D2EHPA + organic solvent were measured in the temperature range of 303.15-333.15 K and 0.1 MPa. The common organic solvents, having different dielectric constants, namely kerosene (2.0), n-heptane (1.92), chlorobenzene (5.62) and 1-octanol (10.3) were employed in this work. The experimental density and viscosity data were validated employing Nasrifar-Moshfeghian (NM) equation of state (EDS) and Vogel-Fulcher-Tammann (VFT) equation: data correlations proved to be a good fit according to the RAD values in the range of 0.01-2.00%. Further, the excess molar volume and viscosity deviation were calculated in order to investigate the nature of the solute solvent binary mixtures. For all binary mixtures, the excess molar volume and viscosity deviations have negative deviations from ideality over the temperature range. The strongest interaction of D2EHPA extractant occurred in kerosene solvent affected by its large hydrophobic molar volume. In addition, other thermodynamic properties of mixtures such as apparent molar volume, thermal expansion coefficients, excess Gibbs energy, enthalpy and entropy of activation Of viscous flow were calculated. (C) 2016 Published by Elsevier B.V.