Interfacial properties of mixtures containing supercritical gases

Interfacial tensions of systems comprising water, carbon dioxide and diluent gases at high pressures: Experimental measurements and modelling with SAFT-VR Mie and square-gradient theory

“…The success of the SGT is apparent from the volume of literature covering its application to a large range of fluids, utilizing a similar wide range of underlying fluid theories. The theory has seen applications to, among other areas: liquid-liquid systems [16], polymers [19], associating systems [20][21][22], polar systems [22], (alkane + CO 2 ) systems [23] and (water + gas) systems [24][25][26].…”

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]…”

“…Due to the availability of experimental data for phase equilibria and interfacial tension, this binary mixture is traditionally used as a reference test case for simulating the behavior CO 2 + long or heavy n-alkane mixtures (see for instance Refs. [22,28,34,33]). Accordingly, the mixture has been selected in the present work for testing our approaches and for complementing the work of Gasem at al.…”

“…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.…”

“…For the case of CO 2 + n-C 13 H 28 no experimental or theoretical values are available in the open literature. Finally, bulk phase equilibria and IFTs for CO 2 + n-C 14 H 30 were measured by Gasem et al [12] and theoretically modeled by using the DFT + SAFT-VR EoS [22] and the Square Gradient Theory (SGT) using cubic [26], quartic [28] and SAFT [33,34] EoSs. This paper is organized as follows; we first describe the experimental equipment and measurement details (section 2).…”