Ion-Based SAFT2 to Represent Aqueous Single- and Multiple-Salt Solutions at 298.15 K

Abstract

SAFT2 with individual-ion parameters, referred to as ion-based SAFT2, is used to represent the properties of aqueous electrolyte solutions. A new set of parameters for 5 cations (Li+, Na+, K+, Ca2+, and Mg2+) and 6 anions (Cl-, Br-, I-, NO3 -, SO4 2-,and HCO3 -) is obtained from the fitting of the experimental mean ionic activity coefficients and liquid densities of 24 aqueous single-salt solutions at 298.15 K. The ion parameters are universal and transferable to different salts containing the same ion. Because of the peculiar segment energy of K+, a mixing rule with a binary interaction parameter for the segment energy describing the short-range interactions between K+ and other cations is needed. The binary interaction parameter is derived from the osmotic coefficients of chloride solutions. The predictions of the osmotic coefficients, vapor pressures, and liquid densities of single- and multiple-salt solutions including seawater (brine) are found to agree with experimental data.

Prediction of molar volume and partial molar volume for CO2/ionic liquid systems with heterosegmented statistical associating fluid theory

“…In fact, we did not expect the cation to have a large value because we did not explicitly treat the long-range electrostatic interaction in our model. However, it is interesting to note that the same trends were also observed in our previous works on inorganic salts [44,47,48].…”

Thermodynamic and Dynamic Investigation for CO2 Storage in Deep Saline Aquifers

“…The model was proposed as SAFT1-RPM first, and then improved to SAFT2. The detailed description for both SAFT1-RPM and SAFT2 was in references [8,[16][17][18][19][20].…”

“…the well depth of the association site-site potential ε, and the parameter related to the volume available for bonding κ. For ions, there is one additional parameter, effective diameter d. The mixing rules are followed those in our previous work [8,[16][17][18][19]20 ].…”

“…We have been working on the related studies for several years and obtained promising results [8,[16][17][18][19][20][21]. Thermodynamic study is on the basis of statistical associating fluid theory (SAFT) EOS, and preliminary kinetics investigation is based on t he non-equilibrium thermodynamics with chemical potential gradient as driving force.…”

Modeling of aqueous electrolyte solutions based on perturbed-chain statistical associating fluid theory incorporated with primitive mean spherical approximation

“…In addition, Tan et al [25] presented the SAFT2-RPM EoS in which their SAFT1-RPM EoS is modified to be applicable to the bivalent ions. In particular, Ji and Adidharma [26] developed the ion-based SAFT2 EoS, based on the SAFT2-RPM proposed by Tan et al [25]. The ion-based EoS is characterized with the individual ion parameters which are applicable to different salts containing the same ion.…”