Journal of Chemical & Engineering Data最新文献

In this study, the solid–liquid equilibrium solubility and solvent effects of α-aminoisobutyric acid in 13 monosolvent systems (water, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, N,N-dimethylformamide, acetonitrile, acetone, ethyl acetate, 2-butanone, and methyl acetate) were reported at the pressure of 101.2 kPa (at T = 283.15–323.15 K). Among the 13 monosolvents, the solubility increased with the increase of absolute temperature, the order is water > N,N-dimethylformamide > methanol > ethyl acetate >2-butanone > ethanol > n-propanol > n-butanol ≈ n-pentanol > isopropanol > acetone > methyl acetate ≈ acetonitrile. The modified Apelblat model, Yaws model, Margules model, and nonrandom two-liquid (NRTL) model were employed to correlate the experimental solubility, and the OriginPro 2019b software was used for analysis and fitting, and the fitting results of the four models were all satisfactory. In addition, through a comparison of the average ARD and root-mean-square deviation (RMSD) values of the four models, the Yaws model achieved the best correlation result. Hirshfeld surface analysis (HS) and molecular electrostatic potential surface (MEPS) performed by the CrystalExplorer software and Gauss 5.0 program were used to determine the internal interactions within α-aminoisobutyric acid solutions. In addition, Hansen solubility parameters (HSPs) were utilized to analyze the solubility behavior. Furthermore, mixing thermodynamic characteristics of α-aminoisobutyric acid in selected solvents were calculated by the NRTL model, which revealed that the mixing process was spontaneous and entropy-driven. These experimental results could be utilized for the purification, crystallization, and industrial applications of α-aminoisobutyric acid, as well as similar substances.

Isobaric vapor–liquid equilibrium (VLE) data were collected for three binary mixtures: pentamethylene diisocyanate and 5-chloropentyl isocyanate, pentamethylene diisocyanate and chlorobenzene, and 5-chloropentyl isocyanate and chlorobenzene. These measurements were conducted using a modified Rose-type recirculating still, within a temperature range of 336.15–435.15 K and at 10 kPa. The uncertainty of temperature and pressure was divided into 0.6 K and 0.1 kPa. No azeotropic behavior was observed during the experiments. The experimental results were regressed using the maximum likelihood function and were correlated with three activity coefficient models: NRTL, Wilson, and UNIQUAC, from which the corresponding binary interaction parameters were estimated. Data of all binary systems passed thermodynamic consistency tests, including the Herington area test and the Van Ness point method. The root-mean-square deviations of the vapor phase mole fraction and equilibrium temperature were less than 0.0107 and 0.82 K, which demonstrated that the experimental data were well correlated with all three models.

This study investigates the phase equilibrium behavior of the isopropyl acetate (IAC)-isopropanol (IPA) azeotrope system at 101.3 kPa in the presence of three different imidazolium-based ionic liquids (ILs) as entrainers, 1-butyl-3-methylimidazolium acetate ([BMIM][Ac]), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][NTf₂]), and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIM][NTf₂]). First, according to the measured vapor–liquid equilibrium (VLE) data of the binary system IAC(1)-IPA(2) and the ternary system IAC(1)-IPA(2)-ILs(3), [BMIM][Ac] in the ternary system produces a strong salting-in effect on IPA, while [BMIM][NTf₂] and [HMIM][NTf₂] produces a salting-in effect on IAC, and the effect of [BMIM][Ac] is much stronger than [BMIM][NTf₂] and [HMIM][NTf₂]. This work uses the nonrandom (local) two-liquid equation to correlate the VLE data. The mole fractions of [BMIM][Ac], [BMIM][NTf₂], and [HMIM][NTf₂] required to exactly eliminate the azeotropic point of the IAC-IPA system are 0.035, 0.144, and 0.206, respectively.

In this experiment, we used eight pure solvents and three binary solvents to measure the solubility data of adefovir (AF) in the temperature range of 278.15–323.15 K. To ensure the accuracy of these data, we employed thermodynamic models to fit the data and assess their accuracy. We observed that the solubility of adefovir in all solvents increased with the temperature. Among the pure solvents, DMF exhibited the highest solubility of adefovir, while the solubility of adefovir in toluene was the lowest. The solubility of adefovir improved as the positive solvent’s molar fraction increased in the binary solvent mixtures. All five models effectively fitted the solubility data, and the reliability of the results was confirmed by comparing the relative average deviation (RAD) and the root-mean-square deviation (RMSD) for each model. In conclusion, the modified Apelblat model was found to be more effective for pure solvents, while the CNIBS/R–K model demonstrated superior performance for binary solvents. Additionally, analysis of the pure solvent parameters using the KAT-LSER model revealed that the hydrogen bonding alkalinity of the solvents was the main factor influencing the solubility of adefovir in the solvent.

Liquid–liquid equilibrium data for ternary systems of geraniol + ethanol + water and citronellol + ethanol + water were obtained experimentally under atmospheric pressure and at temperatures of 303.15 and 323.15 K. The experiment was carried out using a jacketed equilibrium cell as a reference for citronella oil derivative component purification by the solvent extraction method. The experiment was held for 4 h stirring and 20 h settling before the organic and aqueous sample phases were taken to be analyzed. Gas chromatography was used to analyze the equilibrium samples of the organic and aqueous phase compositions. The experimental data were found to be thermodynamically consistent with the Othmer–Tobias and Bachman–Brown correlations. The data were well-correlated by NRTL and UNIQUAC models with rmsd ranging from 0.0086 to 0.0164 and following the type 1 classification by Treybal.

Micellar aqueous two-phase systems (ATPSs) find prominent applications in the extraction of hydrophobic solutes owing to their low interfacial tension. In this study, we investigated the liquid–liquid equilibrium (298.15 T/K and 101.325 P/kPa) and phase-forming abilities of organic (trisodium-citrate dihydrate and potassium sodium tartrate tetrahydrate) and inorganic (ammonium sulfate and ammonium phosphate dibasic) salts with an amphiphilic surfactant, Triton X-100. The experimental binodal curves for four micellar ATPSs were determined employing the cloud point method, and tie-line compositions were calculated using the gravimetric approach. The experimentally determined equilibrium data were thermodynamically correlated using effective excluded volume theory. For tie-line data accuracy, the Othmer–Tobias and Bancroft equations were used, and the corresponding correlation coefficients were reported. The phase separation ability of organic and inorganic salts was analyzed by using the Hofmeister series. Furthermore, we explored the effectiveness of micellar ATPSs in extracting hazardous pollutants from the textile industry, Rhodamine B (RB) and Chromium(VI) (Cr⁶⁺). Extraction experiments showed RB partitioning almost entirely (%E ∼ 99%) into a surfactant-rich phase, and ammonium sulfate-based ATPSs offered the highest extraction for the Cr⁶⁺ metal ion (% E = 81%). This study showcases the cost-effective way for the extraction of harmful hydrophobic industrial pollutants.

The densities, refractive indices, viscosities, surface tensions, and speed of sound of [C_neim][PF₆] (n = 3, 4) and [C_nmim][PF₆] (n = 4, 5, 6, 7, 8, 9) were experimentally determined and analyzed at temperatures ranging from 293.15 to 343.15 K, under atmospheric pressure conditions. All of the properties decrease as the temperature increases, as expected, with viscosity being the most influenced by the temperature change. The density, speed of sound, surface tension, and refractive index are estimated by using linear correlation as a function of temperature, whereas viscosity is correlated by using the well-known Vogel–Fulcher–Tammann (VFT) equation. The corresponding coefficients of thermal expansion were determined by using the experimental density data. Moreover, the Laplace–Newton equation was used to calculate the isentropic compressibility. Furthermore, the influence of anion type and alkyl chains on the thermophysical properties of the studied ionic liquids is studied. Based on the findings, the physical properties of the investigated ionic liquids are greatly influenced by the nature of the anion, while the alkyl chain has less significance. As the alkyl chain length increases, the density, speed of sound, and surface tension all decrease. Viscosity and refractive index, on the other hand, exhibit diametrically opposed behavior. Furthermore, a comparison between theoretical models for density, surface tension, speed of sound, and experimental values obtained from this work is discussed.

This work reports Fick diffusion coefficients D₁₁ and thermal diffusivities a in binary liquid mixtures containing cyclohexane, n-decane, n-heptane, toluene, isobutylbenzene, 1-methylnaphthalene, methanol, ethanol, or acetone. The mixtures are investigated by dynamic light scattering at temperatures T = 298, 348, and 423 K close to saturation conditions. Besides equimolar composition, toluene-based binary mixtures with methanol, ethanol, or cyclohexane are investigated at toluene mole fractions between 0.1 and 0.9. The average relative expanded experimental uncertainties (k = 2) for D₁₁ and a are 5.3 and 8.3%. For the studied systems, the influence of molecular characteristics on the diffusivities as a function of T and composition is discussed. While D₁₁ clearly depends on the molecular structure of the mixture components, i.e., alkane chain length, aliphatic or aromatic rings, or hydroxyl and carbonyl functional groups, such relationships were not resolvable for a within the experimental uncertainties. For mixtures containing the polar species methanol, ethanol, or acetone, an influence of hydrogen bonding on D₁₁ was found. In general, the identified structure–property relationships agree with those reported in the literature for similar systems. Furthermore, a comparison of the present D₁₁ and a data with corresponding literature data is performed.