Journal of Solution Chemistry最新文献

The mean ionic activity coefficients of NaCl in the system {yNaCl + (1 − y) NaH₂PO₄}(aq) were determined by electromotive force measurements (EMF) in two series in which the NaCl ionic strength fraction was as follows: I series, y = (0.2368; 0.3101; 0.4101; 0.5051; 0.6090; 0.7775; 0.9039) and II series, y = (0.1998; 0.4005; 0.5993; 0.8105) in the range of total ionic strength of the solution I_m = (0.0887–1.0081) mol·kg⁻¹ at a temperature T = 298.15 K. A cell of the Na–ISE∣({text{NaCl}(m}_{text{NaCl}})), ({text{Na}}{text{H}_{2}text{PO}}_{4}{(m}_{{text{Na}}{text{H}_{2}text{PO}}_{4}}))∣Ag∣AgCl type was utilized for the EMF measurements. The standard electrode potential of the electrode pair was estimated as E⁰ = 23.2288 mV. The values of the mean ionic activity coefficient of NaCl in the mixed electrolyte solution, ({gamma }_{pm text{NaCl}}), were determined using the Nerst equation. The experimental results from this study were treated with the models proposed by Pitzer, Clegg and Scatchard to estimate the mixture parameters. A high degree of agreement was found between the experimental and calculated values of the mean ionic activity coefficients of NaCl with an average standard deviation of fit being (text{s}.text{d}.left({gamma }_{pm }right)sim) 2.5·10^–3 for each of the three models. The values of the osmotic coefficients of the system {yNaCl + (1 − y)NaH₂PO₄}(aq) were estimated based on the determined model parameters and compared with literature data. Negligible differences were found between the estimated and experimental values of the osmotic coefficients.

In this review, we aim to present the unique physicochemical properties of protic ionic liquids (PILs) composed of alkyl (= hexyl, octyl, and 2-ethylhexyl) ethylenediaminium cations paired with trifluoroacetate (= TFA), trifluoromethanesulfonate (= TFS), bis(trifluoromethylsulfonyl)imide (= TFSA) anions, and acyl (= butanoyl, hexanoyl, octanoyl, decanoyl, and dodecanoyl) alaninate anions. Our primary objective is to evaluate the performance of these PILs, particularly those with hexyl- or 2-ethylhexylethylenediaminium cations, which demonstrate the potential for forming room-temperature PILs with lower viscosity and higher electroconductivity. Furthermore, we investigate the thermal degradation temperatures, revealing that PILs with TFSA anions possess the highest thermal stability, followed by TFS, acylalaninate, and TFA anions. The distinctive chelating ethylenediamine moiety in the cationic unit of these PILs, especially in AA-PILs with acylalaninate anions, enhances their ability to encapsulate transition metal ions, making them highly effective for metal ion coordination, with a preference order of Cu²⁺ > Co²⁺ > Ni²⁺. This study underscores the potential of these PILs for applications in metal-containing wastewater treatment and the synthesis of metal nanomaterials, highlighting their versatility and importance in these fields.

This study investigated the solid–fluid and vapor–liquid equilibrium of varying the molar fraction of ketoprofen in binary system (CO₂ + ketoprofen), 3.14 × 10^–5, 4.70 × 10^–5 and 8.11 × 10^–5, and the concentration of ketoprofen in ternary system (CO₂ + ethanol + ketoprofen), 0.05073 and 0.10277 mol_Ketoprofen·kg_ethanol⁻¹, on a CO₂-free basis for both systems. The aim was to study the solubility of ketoprofen at different molar fractions and predict its behavior over a wide range of temperatures and pressures by means of thermodynamic modeling. Experiments were conducted as a function of temperature from 313 to 333 K and pressure up to 14 MPa, using a visual synthetic static method with a variable volume cell. The collected data highlight an increase of the ketoprofen solubility with the temperature, while a ketoprofen content has a low impact on the bubble point pressure of the tested ternary system. Data were then correlated by using the thermodynamic modeling employed the Redlich–Kwong–Peng–Robinson equation of state (RK–PR EoS) with quadratic mixing rules for fluid phases and a pure solid model for ketoprofen. Then, a number of complete isopleths at set global composition were computed for the CO₂ + ketoprofen binary system being indicated solid–fluid, solid–fluid–fluid, and fluid–fluid regions. The obtained results suggest that the thermodynamic models used in this work were able to describe the experimentally observed phase behavior.

Graphical Abstract

Chiral interactions play a crucial role in both chemistry and biology. Understanding the behavior of chiral molecules and their interactions with other molecules is essential, and chiral interactions in solutions are particularly important for studying chiral compounds. Chirality influences the physical and chemical properties of molecules, including solubility, reactivity, and biological activity. In this work, we used isothermal titration calorimetry (ITC), a powerful technique for studying molecular interactions, including chiral interactions in solutions. We conducted a series of ITC measurements to investigate the heat of dilution and the heat of racemization of several amino acids (Asparagine, Histidine, Serine, Alanine, Methionine, and Phenylalanine). We also performed ITC measurements under different solute concentrations and temperatures to examine the effects of these parameters on chiral interactions, as well as the heat of dilution and racemization. The results of our measurements indicated that the heat of dilution, specifically the interactions between the solvent (water) and solute (chiral molecules), had a significant impact compared to the chiral interactions in the solution, which were found to be negligible. This suggests that the interactions between chiral molecules and the solvent play a more dominant role in determining the overall behavior and properties of the system. By studying chiral interactions in solutions, we can gain valuable insights into the behavior of chiral compounds, which can have implications in various fields, including drug design, chemical synthesis, and biological processes.

Acetylene (C₂H₂) is a colourless and odourless gas, making leak detection challenging. It can react with certain metals, such as copper and silver, to form highly sensitive and explosive compounds. Therefore, designing a highly efficient C₂H₂ sensor is of paramount importance for environmental and safety reasons. Utilizing deep eutectic solvents (DESs) offers a cost-effective and efficient method for sensing and removing C₂H₂. Theoretical exploration of a DES composed of choline chloride and amino acid was conducted using density functional theory (DFT) calculations to assess its efficacy in adsorbing C₂H₂. The DESs were optimized, and calculations were executed using Gaussian 16 software with the 6-311G* (d,p) basis set and the B3LYP method. The DES exhibited anticorrosive and antioxidant properties, which could enhance the stability and longevity of the sensor, especially in harsh environments. Among the DES systems studied, the system labelled 17A exhibited the most negative Gibbs free energy as determined by the DFT calculations. The change in optimization energy for the 10AAc system in the gaseous state was found to be − 0.3054 kJ·mol^–1. Additionally, Molecular Dynamics (MD) simulations were performed to analyse the interactions of the DES-C₂H₂ complex with the lowest optimization energy (10AAc) using Root Mean Square Deviation (RMSD) and Root Mean Square Fluctuation (RMSF) trajectories.

Graphical Abstract

Knowledge of the values of the thermodynamic functions of natural minerals of transition elements has important applications in the study of the processes of their formation and geochemical migration with groundwater; when developing methods to prevent corrosion of non-ferrous alloys in fresh and sea water; when immobilizing heavy metals in mine drainage and industrial waters, etc. Also, these values are in demand when calculating reactions and developing methods for producing synthetic analogs of minerals, many of which exhibit magnetic, catalytic, photochemical, and other properties. However, in scientific literature, there is a lack of detailed data on the thermodynamic properties of nickel hydroxysalts. A sample of basic nickel carbonate with the theoretical formula Ni₃[CO₃](OH)₄·3H₂O was obtained using the hydrothermal synthesis method. The structure of the compound was verified by X-ray diffraction and infrared spectroscopy. Experiments were carried out on sample dissolution in order to measure the solubility constant (solubility product): log₁₀ K_SP =  − 45.8 ± 1.8. Based on the data obtained, the thermodynamic parameters of the reaction of dissolution of the compound were determined and the main thermodynamic functions were determined: Gibbs free energy of formation Δ_fG° =  − 1554 ± 6 kJ·mol⁻¹; enthalpy of formation Δ_fH° =  − 1798 ± 9 kJ·mol⁻¹; standard entropy S° = 260.6 ± 7.8 J·mol⁻¹·K⁻¹.

The viscosities of the quinary system NaCl + KCl + CaCl₂ + MgCl₂ + H₂O and its binary subsystems are measured in the temperature range of 288.15 K-308.15 K. The viscosities of binary solutions of MgCl₂, NaCl, and CaCl₂ increase with the increase in concentration. In contrast, for the binary solution of KCl, the viscosity decreases with increasing concentration at low temperature and low concentration. The extended Jones–Dole model that incorporates higher-order term parameters is used to fit the viscosity of binary solutions, with a maximum Average Relative Deviation (ARD) of 1.42%. By comparing the values of the Pearson correlation coefficients, it is found that MgCl₂ has the most significant impact on the viscosity of the quinary system MgCl₂ + KCl + NaCl + CaCl₂ + H₂O, while the impact of KCl is the least. The modified extended Jones–Dole model, with the introduction of parameter G_i, can accurately predict the quinary system, resulting in a maximum AAD value of 0.63%. Moreover, the Hu model is also applied to predict the viscosity of the quinary system, achieving a maximum ARD value being 1.54%. Compared to the Hu model, the modified extended Jones–Dole model performs better. The viscosity calculation models for the quinary system MgCl₂ + KCl + NaCl + CaCl₂ + H₂O in this study contribute key parameters for the design and optimization of the potassium chloride production process.

A polemic is given regarding several of the volumetric properties that Touazi and coworkers reported in their published paper. A critical analysis of the published excess molar volumes for binary decalin + tridecane and decalin + tetradecane mixtures revealed that the values determined at low decalin mole fraction compositions were not consistent with values measured at higher decalin compositions. The analysis further showed that the excess molar volumes for the decalin + tridecane and decalin + tetradecane systems differ significantly from published data reported by independent research groups for binary decalin mixtures containing both smaller (C₅ to C₁₂) and larger (C₁₆) linear alkane molecules.

Calculations of hydration energies are extremely important in physical, chemical, and life sciences, and therefore their values need to be accurately determined if these energies were to be used to derive the proper and correct physico-chemical mechanisms. Here, we prove the existence of absolute correlation between ionization and hydration energies for transition metal cations. The said absolute correlation can be exploited in an unambiguous manner to verify the calculated hydration energies for divalent and trivalent transition metal cations.

The density and viscosity of the pseudo-binary mixtures of eutectic solvent (ES) composed of choline chloride and ethylene glycol ([ChCl/EG]) with dimethylsulfoxide (DMSO) were measured. In order to understand the effect of the mole ratio of ChCl:EG, two ChCl/EG ESs with the mole ratio of 1:3 and 1:4 (abbreviated as [ChCl/EG]_(1:3) and [ChCl/EG]_(1:4) in this work) were prepared. The measurements were carried out by digital vibrating U-tube density meter and Ubbelohde capillary viscometer from 303.15 to 323.15 K at atmospheric pressure (98.5 kPa). The Jouyban–Acree model was applied to correlate the experimental density and viscosity data of DMSO/[ChCl/EG]_(1:3) and DMSO/[ChCl/EG]_(1:4) mixtures. In addition, based on the experimental data, the derived properties of the mixtures, such as excess molar volume and viscosity deviation, were calculated. The comparison and analysis of excess molar volume and viscosity deviation for DMSO/[ChCl/EG]_(1:2) reported in literature and the results obtained in this work were carried out.