Density and Viscosity for Binary Mixtures of the Ionic Liquid 1-Butyl-3-methylimidazolium Tetrafluoroborate with 2-Propanol, N,N-Dimethylacetamide and N,N-Dimethylformamide at 293.15–323.15 K: Experimental and PC-SAFT Modeling

Abstract

For three binary mixtures composed of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) with 2-propanol, N,N‑dimethylacetamide (DMA) and N,N‑dimethylformamide (DMF), the values of the experimental density and viscosity over the whole composition range for T = (293.15 to 323.15 K) are reported. Excess molar volume $$\mathop V\nolimits_{{\text{m}}}^{{\text{E}}}$$, partial molar volume $$\overline{{V_{i} }}$$, and the deviation in viscosity $$\Delta \eta$$ are calculated and explained in order to clarify the intermolecular interactions among the species in the mixtures. For all of the binary mixtures, the negative values of $$\mathop V\nolimits_{{\text{m}}}^{{\text{E}}}$$ and $$\Delta \eta$$ were fitted with the Redlich–Kister polynomial function. An increase in temperature decreases the values of $$\mathop V\nolimits_{{\text{m}}}^{{\text{E}}}$$ and increases the values of $$\Delta \eta$$. The results have been discussed regarding binary interaction forces and the formation of a complex between dissimilar molecules. For the correlation and prediction of the binary system densities, perturbed chain statistical associating fluid theory (PC-SAFT) was used. The results obtained from this theory are consistent with the experimental data.