Application of the Peng-Robinson equation of state to calculate interfacial tensions and profiles at vapour-liquid interfaces

Interfacial properties of selected binary mixtures containing n-alkanes

“…In fact, our predictions show, far from its critical state, similar accuracy than other EoS models [21,22,32]. However, when the mixture approaches to its critical state, the EoS fails to predict accurately the VLE behaviour.…”

“…In principle, the Helmholtz energy density can be described from any equation of state (EoS), with the consequence that a single EoS can be used to predict both phase equilibrium and interfacial properties. Previous works demonstrated that the combination of the SGT with cubic type EoS [6][7][8][20][21][22][23][24][25][26][27] as well as molecular based EoS [9,[28][29][30][31][32][33] models is promising for correlating and/or predicting interfacial properties in some pure hydrocarbon and hydrocarbon mixtures in a wide range of temperatures, pressures and concentrations. Both the SGT and available EoS models require at some stage experimental data for pure component parameter fitting.…”

High-pressure densities and interfacial tensions of binary systems containing carbon dioxide+n-alkanes: (n-Dodecane, n-tridecane, n-tetradecane)

“…Invoking the SGT, the interfacial tension of a binary mixture, γ, is given by the following integral expression: [23][24][25][26][27][28][29][30][31][32][33][34][35]66,67]…”

“…On the other hand, theoretical descriptions of these mixtures have been made by employing Density Functional Theory (DFT) [13,14,22], Density Gradient Theory (DGT) or Square Gradient Theory (SGT) [23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38]. Furthermore, molecular simulations based either on Molecular Dynamics or Monte Carlo schemes have also been employed [19,30,31,39,40,41] to garner information on the interfacial properties of these systems.…”

Classical density functional theory for the prediction of the surface tension and interfacial properties of fluids mixtures of chain molecules based on the statistical associating fluid theory for potentials of variable range

“…At about the same time, Poser and Sanchez 27 combined a lattice theory with DGT to describe the interfacial tension of hydrocarbon mixtures and polymeric systems. Peters and collaborators have made extensive use of the density gradient approach with the PR EOS or with the Associating-Perturbed-Anisotropic-Chain Theory (APACT) to study binary and ternary mixtures of carbon dioxide + butane + decane 28,29 , water + benzene 30,31 , water + ethanol + hexane 31,32 , and gas condensates of n-alkane mixtures 33 . Similar studies with cubic EOSs have been made to describe the interfacial tension of a wide variety of mixtures including: light gases (carbon dioxide, nitrogen or methane) and hydrocarbons [34][35][36] ; refrigerants, nitrogen, argon, alkanes and carbon dioxide 37 ; and associating and non-associating mixtures 38,39 .…”