Generalized LIQUAC model for the single‐ and mixed‐solvent strong electrolyte systems

Research on the thermodynamics of electrolytes is timeless, and modeling an electrolyte solution might be considered to be a golden oldie, which was, is, and will be important in the design of processes and new materials in the future. The reason is that electrolytes play important roles in different scientific disciplines, such as material development, technical processes (chemical industry, biotechnology, and pharma and food industries), and most recently the energy sector. Closely connected is the further development of advanced thermodynamic models. The age of digitalization requires robust physical models as the basis for static and dynamic process modeling, and that will provide the basis for surrogate approaches in future machine learning developments. This all brings thermodynamic modeling to a consideration of its most important feature. There are many thermodynamic approaches which have been developed to correlate, model, and predict the properties and phase behavior of electrolytes. Usually, this has been very successful for aqueous electrolyte solutions. However, for solutions with poor water content, electrolyte modeling is challenging. This mini-review summarizes the recent advance of thermodynamic models for electrolyte solutions in a water-poor medium and suggests the required theoretical framework.

Section: ■ Application Of Thermodynamic Models To Properties and Phas...mentioning

confidence: 99%

Thermodynamic g^E Models and Equations of State for Electrolytes in a Water-Poor Medium: A Review

Held

2020

“…A number of models have been developed for calculating solid−liquid equilibria of mixed-solvent electrolyte systems. Some examples are the electrolyte NRTL model, 19,20 the extended UNIQUAC model, 21,22 the LIQUAC model, 23 the Pitzer−Simonson− Clegg (PSC) model, 24 and the mixed-solvent electrolyte (MSE) model. 25 …”

Section: Introductionmentioning

confidence: 99%

Solubility Measurement and Modeling for the NaCl–NH₄Cl–Monoethylene Glycol–H₂O System from (278 to 353) K

Zeng

2015

The solubilities of NH 4 Cl and NaCl in the mixtures of monoethylene glycol (MEG) and water were determined, respectively, in the temperature range of (278 to 353) K by a dynamic method. The NaCl− NH 4 Cl−MEG−H 2 O system with MEG mole fraction of 0.30 on a salt-free basis was also investigated from (278 to 353) K to determine its phase equilibrium as a function of temperature and the concentration of electrolytes. The solubilities of both NH 4 Cl and NaCl in the MEG−H 2 O mixtures were found to decrease with the addition of MEG and the increasing concentration of the secondary electrolyte. The results show that the increment of temperature causes a marked increase in the solubility of NH 4 Cl but only has a slight impact on the solubility of NaCl. The mixed-solvent electrolyte (MSE) model was applied to model solid−liquid equilibrium for the system containing NaCl, NH 4 Cl, MEG, and H 2 O. Binary interaction parameters for MEG−NH 4 + , MEG−Na + , and Na + −NH 4 + were newly determined by regressing the experimental data. The MSE model with new parameters presented very high accuracy to calculate solubilities for the NaCl−NH 4 Cl−MEG−H 2 O system. The average absolute relative deviations (AARD) between the prediction and the experimental solubility are 0.75 and 0.88% for NH 4 Cl and NaCl, respectively.

“…21 Another example is the LIQUAC model which is derived from the UNIQUAC model. 22−24 Li et al 23 used the LIQUAC model to represent the solubility of a salt (NaCl, KCl, NaBr, KBr, and so on) in a binary solvent mixture (water + methanol, water + ethanol). Recently, Wang et al proposed a so-called mixedsolvent electrolyte (MSE) model, which is capable of estimating the phase equilibria of electrolytes in water, organic, or mixed solvents.…”

Section: ■ Introductionmentioning

confidence: 99%

Determination and Modeling of MgCl₂ Solubility in Methanol, Ethanol, 2-Propanol, and Their Mixtures from 283 to 343 K

Zeng

Wang

2016

MgCl2-supported Ziegler–Natta catalyst plays an important role in polyolefin industry. The solubility of MgCl2 in various alcohols has been studied to understand the mechanisms involved in the preparation of the catalyst. The solubility of anhydrous MgCl2 in methanol, ethanol, and 2-propanol and their mixtures was measured by a dynamic method at temperatures from 283.2 to 343.2 K. The solubility was found to increase with increasing temperature, but the increasing rate was dependent on the composition of solvent. In the single alcohol, the solubility value of MgCl2 is under the order of methanol > ethanol > 2-propanol at room temperature. Solubilities of MgCl2 in the mixtures of methanol + ethanol, methanol + 2-propanol, and ethanol + 2-propanol are all larger than that in the single alcohol. Three solid phases, including MgCl2·6CH3OH, MgCl2·6C2H5OH, and MgCl2·4(CH3)2CHOH, were found in the equilibrated solids by XRD characterization. The mixed-solvent model (MSE) embedded in the OLI software was applied to model the experimental solubility data. The log K SP for the dissolution reaction of MgCl2·6CH3OH, MgCl2·6C2H5OH, and MgCl2·4(CH3)2CH OH at 298.2 K were determined to be −11.5078, −13.0943, and −10.6139, respectively.