Modeling of viscosities in extended pressure range using SAFT + Cubic EoS and modified Yarranton-Satyro correlation

The current study is a step toward developing an approach with improved extrapolation capability and predictive potential in modeling viscosities. A modified Yarranton-Satyro correlation that relates viscosities to densities has been coupled with SAFT + Cubic EoS. Having three adjustable parameters, the proposed method allows nearly precise extrapolations of the light gases viscosities to the extreme pressure conditions (up to ∼6 GPa) in wide temperature range. The predictive potential of the proposed method is remarkable as well. For example, using the parameters fitted to the data of carbon dioxide, it allows robust prediction of the elevated pressure viscosities of halocarbons such as R-134a and hexafluorobenzene. In addition, relying on the experimental viscosity of just a single n-alkane, it usually yields reliable estimations of the data of not only n-alkane series but also heavy organic compounds, such as 2,6,10,15,19,23-hexamethyltetracosane, bis(2-ethylhexyl) phthalate, diisodecyl phthalate, and 2-ethylhexyl benzoate in a vast range of values (from single mPa·s to thousands of mPa·s). It has also been demonstrated that using a single set of parameters, the proposed approach can generate accurate predictions of viscosities in a wide pressure range for ionic liquids belonging to similar families, such as [C _xmim][PF ₆] and [C _xmim][BF ₄].