Experimental measurements and modelling of volumetric properties, refractive index and viscosity of selected binary systems with butyl lactate at 288.15–323.15 K and atmospheric pressure. New UNIFAC-VISCO interaction parameters

Abstract

Densities, refractive indices and dynamic viscosities of three binary systems: butyl lactate+1-propanol, butyl lactate+1,2-propanediol and butyl lactate+1,3-propanediol, have been measured in temperature range 288.15–323.15K with temperature step of 5K and at atmospheric pressure. From these experimental data, excess molar volumes, deviation in the refractive index and viscosity deviation were determined and fitted to the Redlich–Kister equation. Considering the calculated results, molecular interactions and mixing behaviour in the investigated binary systems have been analyzed. The excess molar volumes were correlated by the Peng–Robinson–Stryjek–Vera cubic equation of state (PRSV CEOS) coupled with the van der Waals (vdW1) mixing rule and CEOS/GE mixing rule introduced by Twu, Coon, Bluck and Tilton (TCBT). The refractive indices of binary mixtures were calculated by various mixing rules and compared with experimental values. The viscosity modelling was performed by two types of models: predictive UNIFAC-VISCO and ASOG-VISCO and correlative Teja–Rice and McAllister models. For predictive UNIFAC-VISCO model the experimental viscosity data were used to determine the new CH–COO interaction parameter.