Volumetric and viscosity data of 1-iodonaphthalene + n-alkane mixtures at (288.15-308.15) K

Abstract

Density and viscosity measurements have been performed for the systems 1-iodonaphthalene + heptane, or + decane, or + dodecane, or + tetradecane over the temperature range (288.15-308.15) K and at 94 kPa. At this end, a densitometer Anton-Paar DMA 602 and a Ubbelohde viscosimeter were used. Excess molar volumes ($V_m^E$) are large and negative and decrease when the temperature is increased, which reveals that the main contribution to $V_m^E$arises from structural effects. The values of the deviations of dynamic viscosity from linear dependence on mole fraction are also large and negative, indicating that n-alkanes are good breakers of the interactions between 1-iodonaphthalene molecules. Different models were applied for describing viscosity data. The McAllister’s equation correlates well kinematic viscosities. Results are similar when dynamic viscosities ($\eta$) are correlated with the Grunberg-Nissan or Fang-He equations. This means that size effects are not relevant on the mentioned data. The adjustable parameter of the Grunberg-Nissan equation is negative for all the systems at any temperature, a typical feature of systems where dispersive interactions are dominant. This is in agreement with findings obtained in previous studies on similar n-alkane mixtures involving C₆H₅X (X = Cl, Br, I) or 1,2,4-trichlorobenzene or 1-chloronaphthalene. Free volume effects have little influence on the present $\eta$results, well represented by the absolute rate model using residual molar Gibbs energies obtained from the DISQUAC model.