Simultaneous Description of Equilibrium, Interfacial, and Transport Properties of Fluids Using a Mie Chain Coarse-Grained Force Field

We propose an unequivocal top-down strategy to build state independent coarse-grained force fields based on the homonuclear Mie chain model. Then, this approach is applied to predict thermophysical properties (equilibrium, interfacial and transport) of nonassociating fluids from molecular simulations. Following the seminal work of Mejia et al. [Ind. Eng. Chem. Res. 2014, 53, 4131], the proposed top-down strategy is based on an extended corresponding states principle (i.e., requiring the critical temperature, one saturated liquid density and the acentric factor for each compound) enriched by the introduction of one reference viscosity in the parametrization procedure. Molecular simulations of the so-developed coarse-grained model representing various pure fluids (noble gas, n-alkanes, H2S, CO2, etc.) yield excellent results on the whole vapor–liquid equilibrium curve. Critical points, saturated densities, vapor pressures, and surface tensions are accurately predicted. Saturated liquid viscosities are as well correctly predicted, which is an improvement over previous similar coarse-grained models. Using classical Lorentz–Berthelot combining rules, simulations results of the pressure–composition phase diagrams of noble gases mixtures are in good agreement with the experimental ones without additional parametrization. In addition, predictions of densities and viscosities of some liquid binary mixtures of hydrocarbons, including asymmetric ones (CH4 + nC10) for pressure up to 100 MPa, are as good as those obtained on pure fluids. Last, the proposed coarse grained model is able to provide Soret coefficients of Ar–Kr and nC5–nC10 mixtures with good accuracy. All these results confirm the consistency and the robustness of the proposed approach.



Hai Hoang,Stéphanie Delage-Santacreu and Guillaume Galliero


Ind. Eng. Chem. Res., 2017, 56 (32), pp 9213–9226