Universal Quasichemical Models Research Articles

Ternary Liquid–Liquid Equilibrium Data for the N-Formylmorpholine + Toluene + {n-Nonane or n-Decane} Systems at (303.2, 323.2, and 343.2) K and 101.3 kPa

The design and operation of the process to extract aromatics from petroleum intermediates via solvent extraction can be enhanced in terms of efficiency by access to liquid–liquid equilibrium (LLE) data. This study serves to contribute LLE data for a heavy alkane, aromatic, and solvent mixture, which is of limited availability in the open literature. Ternary LLE phase compositions were experimentally measured and thermodynamically modeled for the systems N-formylmorpholine (NFM) + toluene + (n-nonane or n-decane) at 303.2, 323.2, and 343.2 K and 101.3 kPa. The direct analytical method was used to obtain the LLE data using a double-walled glass cell. The phase equilibrium samples were quantitatively analyzed using gas chromatography. The ternary systems were successfully correlated using the non-random two-liquid and universal quasichemical thermodynamic models. The effectiveness of using NFM as an alternative solvent to extract toluene from a mixture containing n-nonane or n-decane was evaluated by determi...

Experimental Determination and Correlation of Liquid–Liquid Equilibria Data for the Ternary Systems of Water + 1-Butanol + Solvents (Isophorone and Mesityl Oxide) at Different Temperatures

Liquid–liquid equilibria (LLE) data for {water + 1-butanol + isophorone} and {water + 1-butanol + mesityl oxide} ternary systems were investigated systematically at different temperatures under atmospheric pressure. The Othmer–Tobias and Bachman equations were applied to analyze the dependability of the experimental LLE data. Selectivities and distribution coefficients were used to evaluate the extractive efficiency of the extractants. The Non-Random Two Liquid (NRTL) and Universal Quasi-Chemical (UNIQUAC) models were applied to correlate the studied systems and were well represented with all root mean square deviations (RMSD) less than 0.2%. Meanwhile, binary interaction parameters among these compounds were acquired during the correlation process.

Quasichemical Approach to pH Shifts in Frozen Phosphate Buffers

Shifts in the pH of buffer solutions upon freezing have received much attention particularly in the life sciences, as such pH variations during freezing may damage biological samples, biomolecules, and pharmaceuticals. The understanding and prediction of the said pH changes upon freezing are essential to utilize buffer solutions in a wide temperature range, including subzero temperatures. Phosphate is of particular importance for aqueous buffer preparation as it covers a wide pH range and displays high biocompatibility. However, the phase behavior and pH changes in phosphate buffers at subzero temperatures are very complex due to the variety of species involved in the phase and acid–base equilibria. This paper focuses on the interpretation of the pH changes in phosphate buffers under freezing conditions using an extended universal quasichemical (EUQ) model. This model has been previously applied to understand the phase behavior (solid precipitation) in phosphate buffers at subzero temperatures but not to the calculation of the pH of the liquid phase (freeze-concentrated solution, FCS) that coexists with ice and salt precipitate. Since the EUQ model provides activity coefficients for all of the components in the system, not only the phase behavior but also the pH value can be estimated. The calculated pH values are compared to experimental values and are interpreted from the viewpoints of salt deposition, salt enrichment in the FCS, and supercooling effects.

Vapor–Liquid Equilibrium for Binary of 1-Butanol + N,N-Dimethylacetamide and Methyl Isobutyl Ketone + N,N-Dimethylacetamide at 101.3 kPa

Vapor–liquid equilibrium data for the binary systems of 1-butanol + N,N-dimethylacetamide and methyl isobutyl ketone + N,N-dimethylacetamide were measured at 101.3 kPa. The vapor–liquid equilibrium experiments of two systems were carried out in the modified Rose vapor recirculating-type equilibrium still. Van Ness and Herington tests were used to check the thermodynamic consistency of the experimental data. After meeting the thermodynamic consistency test, the nonrandom two-liquid, universal quasichemical, and Wilson models were used for correlation and regression of the experimental data. The binary interaction parameters of each model for the two binary systems were obtained. Comparing the equilibrium temperature and vapor-phase mole fraction for the experimental value and the calculated value, it shows that the two models had a good correlation with the experimental data.

Liquid–Liquid Equilibrium Measurements for the Ternary System of Water/2,3-Butanediol/4-Methyl-2-pentanol at Various Temperatures

Liquid–liquid equilibrium (LLE) of a ternary mixture of water, 2,3-butanediol, and 4-methyl-2-pentanol has been measured at three different temperatures (298.2, 308.2, and 318.2 K) under atmospheric pressure. The experimentally measured solubility and tie-line data for the two-phase system were used to construct a ternary phase diagram at each temperature. With the experimental data, the distribution coefficients and separation factors were also calculated and Othmer–Tobias and Hand plots were used to verify the consistency of the measured data. The universal quasichemical (UNIQUAC) and nonrandom-two liquid (NRTL) models were used for the LLE, and the root-mean-square deviation values between the calculated and experimental data were less than 1.21% by the UNIQUAC model and less than 1.96% by the NRTL model, indicating that both model calculations provide excellent agreement with the experimentally measured LLE data in the present study.

Liquid–Liquid Equilibria for Benzene/Thiophene + Cyclohexane/Hexadecane + Deep Eutectic Solvents: Data and Correlation

The experimental liquid–liquid equilibria (LLE) for several systems containing benzene or thiophene + cyclohexane or hexadecane + choline chloride-based deep eutectic solvents (DESs) including mono-, di-, and triethanolamines and mono-, di-, and triethylene glycols were measured at T = 298.15 to 308.15 K and atmospheric pressure. The distribution coefficients (β) and selectivities (S) were calculated to evaluate the efficiency of the studied solvents for aromatics (benzene or thiophene) extraction from nonaromatic phases. Generally, the selectivity values decrease with increasing of the temperature for our studied DESs. The Othmer–Tobias equation was used to ensure the consistency of the obtained LLE data. The nonrandom two-liquid (NRTL) and universal quasi-chemical (UNIQUAC) models were used to correlate the experimental LLE data. The Hansen solubility parameters confirm the performance of the studied DESs for benzene and thiophene extraction. The measured LLE data in this study shows better performance ...

Apparent thermodynamic analysis and the dissolution behavior of levamisole hydrochloride in three binary solvent mixtures

The solubility of levamisole hydrochloride (LH) in binary {methanol (MT) + ethanol (EA), methanol (MT) + 2-propanol (IPA)} solvent mixtures from 283.15 K to 323.15 K and dimethyl sulfoxide (DMSO) + ethanol (EA) from 293.15 K to 333.15 K were obtained under the pressure of 0.1MPa by using a dynamic method. Moreover, the experimental solubility results of LH in this work were correlated well with five thermodynamic models namely “Yaws model, van’t Hoff model, Universal Quasi-Chemical (UNIQUAC) model, non-random two liquid (NRTL) model and general single (GSM) model”. The minimum RMSD and ARD are 0.0064 and 0.17 respectively and they are both calculated with the GSM model. Besides, the apparent thermodynamic properties of LH in the selected binary solvent mixtures were discussed. Analysis results showed that enthalpy-favored mechanism plays a major role in the dissolution process of LH.

Separation of the azeotropic mixture 2-propanol + water employing different imidazolium ionic liquids as solvents

The liquid-liquid equilibria of the ternary systems water (1) + 2-propanol (2) + [emim][Tf2N] (3) and water (1) + 2-propanol (2) + [hmim][Tf2N] (3) at 283.2, 303.2 and 323.2 K and atmospheric pressure were investigated, in order to achieve a better knowledge of the ternary mixture behaviour. The capability of [emim][Tf2N] and [hmim][Tf2N] as solvents in the separation of the azeotropic mixture water + 2-propanol was studied through the distribution coefficient and selectivity, and compared with the results obtained with other ionic liquids in the same azeotropic mixture studied before by our research group. The thermodynamic parameters of both ternary mixtures were calculated by the non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models.

Experimental and Thermodynamic Modeling of Quaternary Aqueous Two-Phase System of Poly Ethylene Glycol, Sodium Tartrate, Water and Penicillin G

In present study, the liquid–liquid equilibrium of the quaternary system of polyethylene glycol (PEG) (with molar masses of 1000, 2000, 6000, and 8000 g·mol−1), sodium tartrate salt, Penicillin G and water at 298 K were investigated. The partitioning of Penicillin G between two aqueous phases was also reported. The extended non random two liquid (NRTL) and extended Universal Quasi Chemical (UNIQUAC) models were used to correlate the experimental equilibrium data. The parameters of these activity coefficient models were optimized for the investigated systems. The results show that the polymer molar mass has a dominant effect on the partition coefficient of Penicillin G. Also, results of both thermodynamic models were very satisfactory and satisfactory predicted the equilibrium concentrations of the components in ATPS. Comparison of the absolute average deviation of the two models shows that the extended UNIQUAC model was superior to the extended NRTL model for correlation and interpolation of phase equilibrium data.

Solubility and mixing thermodynamic properties of levamisole hydrochloride in twelve pure solvents at various temperatures

The solubility of solid compounds and active pharmaceutical ingredient in different solvents is important for its crystallization and purification industry. In this work, by using a laser dynamic method, the solubility of levamisole hydrochloride in methanol (MT), ethanol (ET), isopropanol (IPA), n-propanol (NPA), n-butanol (NBA), 2-butanol (SBA), isobutanol (IBA), n-pentanol (NPT), 3-methyl-1-butanol (IAA) and n-hexanol (NHA) from (283.15 to 323.15) K, dimethyl sulfoxide (DMSO) from (293.15 to 333.15) K and water from (283.15 to 308.15) K were measured under atmospheric pressure. The measured results showed that the experimental solubility of levamisole hydrochloride increased non-linearly with the temperature in the studied pure solvents. The measured solubility data were all correlated by the Yaws model equation, non-random two liquid (NRTL) model equation, universal quasi chemical (UNIQUAC) model equation, Wilson model equation and λh equation. Besides, the logarithm of activity coefficient of levamisole hydrochloride (lnγ1) were calculated with the NRTL model, Wilson model and UNIQUAC model. The maximum relative average deviation (ARD) was 0.2008, the maximum root-mean-square deviation (RMSD) was 0.0089. Basically speaking, the measured solubility data in this study can be well correlated with the five thermodynamic models. Based on the solubility data and Wilson model, the mixing entropy, mixing enthalpy and mixing Gibbs energy were evaluated. The logarithm of the solute activity coefficients lnγ1in the studied saturated solutions were calculated, The positive values of lnγ1 means that the repulsive interactions exist between levamisole hydrochloride and the corresponding solvents (NBA, NPA, NHA, IPA, IBA, SBA and IAA), and the solutions system positively deviate from Raoult’s law; The negative values of lnγ1 means that the attractive interactions exist between levamisole hydrochloride and the corresponding solvents (MT, ET, NPT, DMSO and water), and the solutions system minus deviate from Raoult’s law. This work can give fundamental data for the crystallization and purification of levamisole hydrochloride.

Palmitic-Acid-Based Hydrophobic Deep Eutectic Solvents for the Extraction of Lower Alcohols from Aqueous Media: Liquid-Liquid Equilibria Measurements, Validation and Process Economics.

A new, natural, hydrophobic deep eutectic solvent (NADES) based on DL‐menthol and palmitic acid is adopted for the extraction of alcohols from aqueous phase. DL‐menthol is used as a hydrogen bond acceptor and palmitic acid, being a natural organic acid, as a hydrogen bond donor. The synthesis is carried out by the addition of DL‐menthol and palmitic acid in a defined molar ratio. Physical properties of NADES along with water stability are then measured. Liquid–liquid equilibria (LLE) of lower alcohols, namely, DES (1) + lower alcohols (ethanol/1‐propanol/1‐butanol) (2) + water (3) are carried out at p = 1 atm and T = 298.15 K. LLE results show type‐I phase behavior, where alcohol is preferentially attracted toward DES. The tie lines are then regressed via nonrandom two liquid and universal quasichemical models, which give root mean square deviation (RMSD) in the range of 0.29–0.35% and 0.39–0.75%, respectively. Finally, the quantum‐chemical‐based conductor‐like screening model‐segment activity coefficient is used to predict the tie lines, which gives an RMSD of 2.1–5.2%. A hybrid extractive distillation flowsheet is then used for scale up, process economics, and solvent recovery aspects in ASPEN using DES as a “pseudocomponent.”

Liquid–Liquid Equilibrium Measurements and Correlation for Ternary Systems (Butyl Acetate + 1-Butanol + Ethylene Glycol/1,3-Propanediol/Ethanolamine) at 298.15 K

For separation of the azeotropic mixture butyl acetate and 1-butanol, ethylene glycol, 1,3-propanediol, and ethanolamine were chosen as the extractants. The phase equilibria for the ternary systems (butyl acetate + 1-butanol + ethylene glycol/1,3-propanediol/ethanolamine) were investigated, and the liquid–liquid equilibrium (LLE) data were determined at 298.15 K and 101.3 kPa. During the LLE measurement, the equilibrium was achieved when the prepared ternary mixture was stirred for 2 h and settled for 12 h. To evaluate the extraction capacity of the solvents, the distribution constant (D) and selectivity (S) were calculated. From the comparison of the values of D and S, ethanolamine is the best extractive solvent among the three solvents. In the meantime, the nonrandom two-liquid (NRTL) and the universal quasi-chemical (UNIQUAC) models were applied to correlate the LLE data for the systems. The values of the root mean square deviations between the experimental LLE data and calculated values were less than 0.01. Also, the binary interaction parameters of the NRTL and UNIQUAC models were optimized.

Investigation of liquid–liquid equilibrium of the ternary system (water + 1,6-diaminohexane + 2-methyl-1-propanol or 3-methyl-1-butanol) at different temperatures

Abstract In this study, the LLE data of ternary system (water + 1,6-diaminohexane + 2-methyl-1-propanol) and (water + 1,6-diaminohexane + 3-methyl-1-butanol) were measured at 293.15, 303.15 and 313.15 K under atmospheric pressure. Reliability of the experimental tie-line data was checked by empirical Hand, Othmer − Tobias and Bachman equations. Distribution coefficient (D) and selectivity (S) were calculated in order to investigate capability of the studied organic solvents for 1,6-diaminohexane extraction. The high values of separation factors demonstrated that 2-methyl-1-propanol and 3-methyl-1-butanol were applicable for this purpose. The experimental data were correlated by nonrandom two-liquid (NRTL) and universal quasi-chemical (UNIQUAC) models. The percent-root-mean-square deviation (RMSD) values for NRTL and UNIQUAC models were less than 0.15, which indicated that the experimental data have been sufficiently correlated.

Liquid–Liquid Equilibrium for Ternary Systems of N-Methylformamide + Pyrrole/Indole + Alkanes at 298.15 K: Phase Equilibrium Measurement and Correlation

For the purpose of separating nitrogen compounds, pyrrole and indole, N-methylformamide (NMF) was selected as the extractive solvent. The liquid–liquid equilibrium (LLE) data for {NMF + pyrrole/indole + alkanes} systems were measured at 298.15 K under atmospheric pressure of 101.3 kPa. The triangular diagrams of the above eight systems, {NMF + pyrrole/indole + n-hexane/n-heptane/n-decane/n-dodecane}, were classified as Treybal’s type I. Meanwhile, the nonrandom two-liquid (NRTL) and universal quasi-chemical (UNIQUAC) activity coefficient models were applied to correlate the LLE data, and the UNIQUAC model shows better agreement than the NRTL model. In addition, the distribution constant and selectivity factor were calculated on the basis of the experimental data and utilized to investigate the extraction capabilities of NMF for pyrrole and indole.

Liquid-liquid extraction of methanol from its mixtures with hexane using three imidazolium-based ionic liquids

N-hexane plays a significant role in the industrial manufacturing process of methanol. The separation of n-hexane and methanol is important and difficult due to the azeotropic phenomenon. The objective of this work is to measure the experimental data for the three ternary systems n-hexane + methanol + ionic liquids (1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl), 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide and 1-butyl-3-methylimidazolium hexafluorophosphate) at T = 298.15 K and 101.3 kPa. The COSMO-SAC model was used to calculate the infinite dilution activity coefficients of the eleven ILs in the work and in the literature. The liquid-liquid equilibrium data for the ternary systems were compared with the calculated values obtained using the non-random two liquid and universal quasi-chemical activity models, and the binary interaction parameters of the two models were obtained by regressing the experimental data. Comparing the values of the distribution coefficients and separation factors of the three ILs, 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide showed the best extraction effect. The influence of the alkyl chain length and different anions on the liquid-liquid equilibrium data was discussed.

Experimental Measurement and Thermodynamic Model of Liquid–Liquid Equilibrium for the Ternary System of 1-Dodecanol–Phenol–Water

1-Dodecanol with low solubility in water is a potential solvent to extract phenol from wastewater. The liquid–liquid equilibrium data of the ternary system (1-dodecanol–phenol–water) were measured at 298.15, 313.15, 323.15, 333.15, and 343.15 K under atmospheric pressure. The experimental data were correlated by the nonrandom two liquids (NRTL) and universal quasi-chemical (UNIQUAC) models, and the corresponding binary parameters were obtained. The results show that the two models agree well with experimental values. Comparison of the average values of the root mean squared deviation (RMSD) from both models reveals that the NRTL model is more accurate than the UNIQUAC model. The effect of temperature on the extraction process is discussed, and temperature has little effect on extraction efficiency. The van’t Hoff equation is used to correlate the relationship of distribution coefficient to temperature. The enthalpy change of the extraction process was calculated, and the result shows that extraction of ph...

Liquid–Liquid Equilibrium of the Ternary System sec-Butyl Acetate + sec-Butyl Alcohol + Ethylene Glycol at 298.2, 308.2, and 318.2 K

Liquid–liquid equilibrium (LLE) data for the ternary system sec-butyl alcohol + sec-butyl acetate + ethylene glycol were determined at 298.2, 308.2, and 318.2 K under 101.3 kPa. The extraction capacity was represented by separation factors. Separation factors at the studied temperatures are in the range of 1.33–19.66. Also, separation factors decrease with the rise of temperature in general. The nonrandom two-liquid and universal quasi-chemical models were applied to correlate the experimental LLE data measured, and the corresponding binary interaction parameters were obtained. The overall root-mean-square deviation is less than 0.4%. Also, the reliability of binary interaction parameters was validated by the topological analysis based on the Gibbs tangent plane test using a graphical user interface.

Liquid–Liquid Equilibrium for Systems Containing Epoxidized Oils, Formic Acid, and Water: Experimental and Modeling

AbstractEpoxidized oils are eco‐friendly plasticizers, which are industrially produced through the epoxidation reaction in a formic acid‐hydrogen peroxide autocatalyzed system. The fundamental knowledge to describe the phase equilibrium of systems after epoxidation reaction is lacking, which is crucial for the design of the purification facilities. This work reported experimental data for the liquid–liquid equilibrium of three systems, i.e., epoxidized fatty acid methyl esters + formic acid + water, epoxidized fatty acid 2‐ethylhexyl esters + formic acid + water, and epoxidized soybean oil + formic acid + water, in the temperature range (303.15–348.15) K under atmospheric pressure. The results indicated that the liquid–liquid equilibrium constant of formic acid in the systems followed the order of epoxidized fatty acid 2‐ethylhexyl esters > epoxidized fatty acid methyl esters > epoxidized soybean oil. Moreover, the obtained experimental data were correlated using nonrandom two liquid (NRTL) and universal quasi chemical (UNIQUAC) models. The maximum root mean square deviation (RMSD) values as low as 0.0052 and 0.0263 were estimated using the NRTL and UNIQUAC model, respectively. The NRTL model is more suitable than the UNIQUAC model to describe the liquid–liquid equilibrium behavior of these ternary systems.

Isobaric Vapor Liquid Equilibria for Binary Mixtures of Isoamyl Acetate + Ethyl Acetate at 50 and 100 kPa

In this work new phase equilibria data for the system ethyl acetate + isoamyl acetate at pressures of 50 and 100 kPa are reported. The measures were carried out in the equilibrium apparatus FISCHER LABODEST VLE 602D, which is essentially a dynamic equilibrium cell equipped with a Cottrell recirculation pump. The quality of the experimental information was examined with the Wisniak point criteria because binary mixtures under study offer small deviations from the ideality. The nonrandom two-liquid and universal quasichemical activity models with symmetrical parameters were used to correlate experimental data, and both activity models show good correlation with experiments and can be used in distillation process calculations.

Liquid–Liquid Equilibrium of the System {Peanut Biodiesel + Glycerol + Ethanol} at Atmospheric Pressure

This study reports experimental data for the liquid–liquid equilibrium (LLE) for a {peanut biodiesel (1) + glycerol (2) + ethanol (3)} system at 303.15 K and 323.15 K at atmospheric pressure. Solubility (binodal) curves were obtained by a cloud-point method. The reliability of the experimental data was confirmed using the Hand and Othmer–Tobias correlations. The regression coefficients were above 0.97 for all data sets. The universal quasichemical model was successfully used to correlate LLE data, which showed root-mean-square deviations of 0.99%, indicating accuracy close to experimental uncertainties.