Next Article in Journal
Performance Evaluation of Elimination of Stagnation of Solar Thermal Systems
Previous Article in Journal
Assessment and Prediction of Complex Industrial Steam Network Operation by Combined Thermo-Hydrodynamic Modeling
Previous Article in Special Issue
Numerical Simulation for the Combustion Chamber of a Reference Calorimeter
Open AccessFeature PaperArticle

Assessment of the SM12, SM8, and SMD Solvation Models for Predicting Limiting Activity Coefficients at 298.15 K

1
Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, OH 45056, USA
2
Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06520, USA
*
Author to whom correspondence should be addressed.
Processes 2020, 8(5), 623; https://doi.org/10.3390/pr8050623
Received: 9 April 2020 / Revised: 30 April 2020 / Accepted: 19 May 2020 / Published: 22 May 2020
(This article belongs to the Special Issue Thermodynamics: Modeling and Simulation)
The SMx (x = 12, 8, or D) universal solvent models are implicit solvent models which using electronic structure calculations can compute solvation free energies at 298.15 K. While solvation free energy is an important thermophysical property, within the thermodynamic modeling of phase equilibrium, limiting (or infinite dilution) activity coefficients are preferred since they may be used to parameterize excess Gibbs free energy models to model phase equilibrium. Conveniently, the two quantities are related. Therefore the present study was performed to assess the ability to use the SMx universal solvent models to predict limiting activity coefficients. Two methods of calculating the limiting activity coefficient where compared: (1) the solvation free energy and self-solvation free energy were both predicted and (2) the self-solvation free energy was computed using readily available vapor pressure data. Overall the first method is preferred as it results in a cancellation of errors, specifically for the case in which water is a solute. The SM12 model was compared to both the Universal Quasichemical Functional-group Activity Coefficients (UNIFAC) and modified separation of cohesive energy density (MOSCED) models. MOSCED was the highest performer, yet had the smallest available compound inventory. UNIFAC and SM12 exhibited comparable performance. Therefore further exploration and research should be conducted into the viability of using the SMx models for phase equilibrium calculations. View Full-Text
Keywords: solvation free energy; infinite dilution activity coefficient; limiting activity coefficient; electronic structure calculation solvation free energy; infinite dilution activity coefficient; limiting activity coefficient; electronic structure calculation
Show Figures

Figure 1

MDPI and ACS Style

Roese, S.N.; Heintz, J.D.; Uzat, C.B.; Schmidt, A.J.; Margulis, G.V.; Sabatino, S.J.; Paluch, A.S. Assessment of the SM12, SM8, and SMD Solvation Models for Predicting Limiting Activity Coefficients at 298.15 K. Processes 2020, 8, 623.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop