Journal of Solution Chemistry最新文献

This study presents the development and performance evaluation of polyethersulfone (PES)-based mixed-matrix membranes (MMMs) integrated with dolomite for enhanced CO₂/N₂ separation. Micronized dolomite was calcined at 800 °C to increase surface area and subsequently modified with stearic acid to improve hydrophobicity. The MMMs were fabricated via phase inversion with varying dolomite loadings (0–0.75 wt.%), including a 0.5 wt.% hydrophobic variant. Comprehensive membrane characterization was performed using FESEM, FTIR, contact angle analysis, and zetasizer. Gas permeation tests revealed that the incorporation of hydrophilic dolomite improved CO₂ permeability up to an optimal 0.5 wt.%, after which agglomeration hindered performance. Notably, the membrane containing 0.5 wt.% chemically modified hydrophobic dolomite (PES-5) exhibited the highest CO₂/N₂ selectivity of 8.62, indicating a 57.3% selectivity improvement over pure PES. These values closely approach Robeson’s upper bound, highlighting the filler’s dual role in enhancing selectivity and mitigating water vapor interference via increased hydrophobicity. The results suggest that dolomite, a naturally abundant and cost-effective mineral, can serve as a functional inorganic filler in MMMs, providing a viable pathway for low-cost, high-efficiency CO₂ capture applications.

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The solubility of benzene in aqueous monoethanolamine solutions has been measured at temperatures of 140° and 180 °C at pressures up to 1980 kPa. This study complements earlier work at lower temperatures in this system. The plait points for all temperatures have been determined. Activity coefficients for benzene in water and in 30 wt. per cent MEA have been calculated.

Density and viscosity were measured for aqueous mixtures of monoethylene glycol (MEG), diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol (TeEG) across the full concentration range. Measurements were performed at 293.15, 313.15, and 333.15 K under atmospheric conditions, yielding 222 new data points. Density data were used to calculate excess volumes, revealing negative deviations from ideal behaviour. Temperature and molecular weight significantly influenced these deviations. Temperature-dependent correlations were developed for density, viscosity, and excess volumes, providing valuable insights for industrial applications.

This study systematically investigated the phase equilibrium behavior of 3-nitro-1,2,4-triazol-5-one (NTO) dissolution in acetic acid + water binary solvent systems. Using laser dynamic monitoring under atmospheric pressure (0.1 MPa), dissolution equilibrium data were experimentally determined across a temperature range of 293.15–333.15 K. Maximum dissolution capacity was observed at an acetic acid molar fraction of (x_{mathrm{CH_{3} COOH}} = 0.73) attributed to multilevel hydrogen-bonding synergism between solvent components and solute molecules. To establish generalized predictive models, four thermodynamic frameworks—the Apelblat equation, van’t Hoff temperature correlation, Yaws empirical model, and Jouyban-Acree multivariate regression—were applied, all demonstrating excellent correlation with experimental data (average R² > 0.99). Thermodynamic analysis yielded critical dissolution parameters: standard dissolution enthalpy, entropy, and Gibbs free energy, confirming an entropy-driven dissolution mechanism. The compiled phase equilibrium database and validated models provide theoretical guidance for optimizing NTO crystallization processes in industrial applications, while establishing foundational data for molecular design in multicomponent solvent systems for energetic materials.

Potentiometric data of the ternary VO²⁺-picolinic acid (Pic⁻) complexes with the amino acids: glycine (Gly, L⁻), isoleucine (Ile, L⁻), valine (Val, L⁻), arginine (Arg, L⁻), aspartic acid (Asp, L²⁻), and histidine (His, L⁻) previously determined by our group at 25 °C and 1.0 mol·dm⁻³ NaCl and analyzed using the regular Z_B vs pH data, were re-determined using the reduced formation functions Z_Bfondo and their pH dependence. Visualization of the Z_Bfondo vs pH data trends and details on the stoichiometric composition of the complexes formed in aqueous solution were derived and are presented in this work.

This paper presents the Wilson-NA model to evaluate phase equilibria for mixtures containing not only conventional solvents but also other chemicals, such as ionic liquids, fluorous solvents, deep eutectic solvents, bio-based solvents, and pharmaceuticals. The Wilson-NA model is obtained by simplifying the ratio ({v}_{j}^{text{L}}/{v}_{i}^{text{L}}) in the original Wilson model. Then, the liquid molar volume, ({v}_{i}^{text{L}}), is assumed to be proportional to the number of atoms (NA) other than hydrogen atoms, ({nu }_{i}^{text{NA}}), in the molecule. This originates from the Analytical Solution of Groups model, where the number of segments is evaluated for the combinatorial term. First, the relationship between ({nu }_{i}^{text{NA}}) and ({v}_{i}^{text{L}}), and the ratio for two compounds, ({nu }_{j}^{text{NA}}/{nu }_{i}^{text{NA}}) and ({v}_{j}^{text{L}}/{v}_{i}^{text{L}}), are discussed. Next, we employed the Wilson-NA model to correlate the experimental binary data of vapor–liquid equilibria (VLE) and bubble point pressures, and the accuracy was compared with that from the original Wilson model. The VLE prediction was also extended to some ternary systems just by using the interaction parameters for the constituent binary systems. We also applied the method to a modified version of the Wilson model, proposed by Tsuboka and Katayama, to predict the liquid–liquid equilibria for binary and ternary systems containing compounds with high viscosity, fluorous solvents, and ionic liquids. Finally, the Wilson-NA model was evaluated to solid–liquid equilibria (SLE) for binary systems containing pharmaceutical, terpene, or eutectic solvent, for the purpose of considerations to complex systems.

The current manuscript reports densities, speed of sound, and viscosities of an antiretroviral drug, Raltegravir potassium in water and in aqueous potassium chloride and α-Lactose at temperatures 288.15 K and 318.15 K and at atmospheric pressure over the concentration range of (0.02 to 0.1) mol.kg⁻¹ of Raltegravir potassium. The experimentally obtained data have been used to deduce various thermodynamically derived properties like apparent molar volume of solute (({V}_{phi })), limiting apparent molar volume (({V}_{phi }^{0})), limiting apparent molar volume of transfer (({Delta }_{text{tr}}{V}_{phi }^{0})), thermal expansion coefficient (α*), limiting apparent molar expansibility (({E}_{phi }^{0})), isentropic compressibility (({kappa }_{S})), apparent molar isentropic compression of solute (({K}_{S, phi })), limiting apparent molar isentropic compression of the solute (({K}_{S,phi }^{0})), limiting apparent molar isentropic compression of transfer (({Delta }_{text{tr}}{K}_{S, phi }^{0})), hydration number (({n}_text{H})), relative viscosity (({eta }_{r})), Falkenhagen coefficient (A), Jones–Dole coefficient (B), temperature derivative of B-coefficient( dB/dT), free energy of activation of viscous flow per mole of solvent ( ({Delta mu }_{1}^{0#}),) free energy of activation of viscous flow mole of solute ({(Delta mu }_{2}^{0#}),) Entropy of activation of viscous flow ((Delta {S}_{2}^{0#})) and enthalpy of activation of viscous flow (({Delta H}_{2}^{0#})) and viscosity B-coefficient of transfer, ({Delta }_{tr}B.) The effects of temperature on the interactions between potassium chloride/α-Lactose and aqueous Raltegravir potassium have been studied using these parameters. The drug’s ability to form structures and the interactions between hydrophilic and hydrophobic molecules in these systems are examined.

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Plausible interactions between Raltegravir potassium (left) and KCl/α-Lactose (right)

Dyeing, a critical process in textiles, relies on effective dye-fabric binding for optimal coloration. Surfactants play a key role in this binding, with auxiliaries capable of modulating their interactions and impacting dye adhesion. This study explores the aggregation between cetylpyridinium chloride (CPC) surfactant and crystal violet (CV) dye, by monitoring conductivity changes as a marker for micelle formation. The effects of ethanol (EtOH), 1-propanol (1-PrOH), iso-butanol (iso-BuOH), and urea on CPC micellization in aq. CV solutions were analyzed. The driving forces of micelle formation were assessed through assessment of the critical micelle concentration (CMC), counter-ion binding ((beta)), and thermodynamic parameters such as change in Gibbs free energy (({Delta G}_{text{m}}^{0})), enthalpy (({Delta H}_{text{m}}^{0})) and entropy (({Delta S}_{text{m}}^{0})). Results indicate that increased alcohol and urea concentrations, as well as temperature, lead to elevated CMC values. Negative ({Delta G}_{text{m}}^{0}) values suggest that micelle formation for CPC + CV system is a spontaneous process, while the assessment of ({Delta H}_{text{m}}^{0}) and ({Delta S}_{text{m}}^{0}) reveal the roles of hydrophobic and electrostatic forces. Furthermore, thermodynamics of transfer (({Delta G}_{text{m},text{tr}}^{0}), ({Delta H}_{text{m},text{tr}}^{0}), and ({Delta S}_{text{m},text{tr}}^{0})) and enthalpy-entropy compensation parameters were evaluated and reviewed thoroughly, providing valuable insights for optimizing surfactant and additive usage in dyeing applications.

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The mixtures CH₃(CH₂)_u-1COO(CH₂)_v-1CH₃ (u = 5–13, v = 1,2; u = 1,2,3; v = 3,4; u = 1,2,4, v = 5) + n-alkane have been investigated on the basis of excess molar functions, enthalpy ((H_{{text{m}}}^{{text{E}}})), volume ((V_{{text{m}}}^{{text{E}}})), isobaric heat capacity ((C_{{p{text{m}}}}^{{text{E}}})), and isochoric internal energy ((U_{{V{text{m}}}}^{{text{E}}})), and viscosity data, and by means of different models (Flory, Grunberg-Nissan and Bloomfield-Dewan). Solutions are characterized by weak orientational effects. Large structural effects are encountered in a number of systems, such as those containing pentane. The variation with the ester size of the difference between the standard enthalpy of vaporization at 298.15 K of an ester and that of the homomorphic alkane along an homologous series formed by methyl or ethyl n-alkanoates reveals the existence of structural changes in longer n-alkanoates, which lead to stronger interactions between them. A similar result is obtained from values of cohesive energy density. The variation of (V_{{text{m}}}^{{text{E}}}) values of the corresponding heptane mixtures supports this statement. The observed decrease of (H_{{text{m}}}^{{text{E}}}) for systems with a given n-alkane (heptane, e.g.) seems to be more related to the COO group is more sterically hindered than to interactional effects. The (U_{{V{text{m}}}}^{{text{E}}}) (n) function (n is the number of C atoms in the n-alkane) shows a minimum for systems with esters characterized by (u (ge) 4, v = 1); (u (ge) 7, v = 2), or (u (ge) 1, v = 4,5). A similar dependence of (U_{{V{text{m}}}}^{{text{E}}}) (n) was encountered for n-alkane mixtures involving cyclic molecules (cyclohexane, benzene). This result suggests that certain n-alkanoates, in an alkane medium, can form quasi-cyclic structures. Viscosity data are well described by means of free volume effects only. For systems with butyl ethanoate or methyl decanoate, the variation of (Delta eta)(n) (deviation of dynamic viscosity) is consistent with that of (U_{{V{text{m}}}}^{{text{E}}})(n), which supports the existence of the mentioned cyclic structures in these esters. The Flory model provides poor results on (H_{{text{m}}}^{{text{E}}}) for systems characterized by large structural effects. Results are improved when the model is applied to (U_{{V{text{m}}}}^{{text{E}}}) data.

In recent decades, researchers have increasingly explored alternative fuels to improve emission characteristics without compromising diesel engine performance. Among these, water-in-diesel emulsion (W/D) has gained attention due to its potential to reduce emissions, while enhancing engine efficiency. This review critically examines the effectiveness of W/D emulsions in diesel engines, focusing on their impact on both emission reduction and performance characteristics. Various factors crucial to the commercial viability of W/D are assessed, including stability, viscosity, density, and calorific value. While W/D emulsions generally enhance brake thermal efficiency (BTE) and combustion efficiency, some studies report an increase in brake-specific fuel consumption (BSFC) due to the lower calorific value of the emulsion. Additionally, the use of W/D consistently leads to reductions in nitrogen oxides (NO_x), and particulate matter (PM). However, reported findings vary due to differences in experimental conditions, water content, surfactant types, and emulsion stability. The phenomenon of micro-explosion, which improves atomization and combustion, is also discussed as a key factor influencing W/D performance. This review highlights the need for further research to address inconsistencies in reported results, particularly in optimizing surfactant selection for stability and performance. Future studies should also focus on long-term engine durability, real-world engine testing, and economic feasibility assessments to ensure the commercial adoption of W/D emulsions in diesel engines.