Journal of Solution Chemistry最新文献

Gas capture of pollutants such as SO₂ that occur in flue gas, heavy oil refining and metallurgical processes is a necessary and important topic for the environment. In this work, bubble point pressures are reported for SO₂–dimethyl ether at (298.15–323.15) K, SO₂–1,4-dioxane at (293.15–298.15) K, and SO₂–polyethylene glycol dimethyl ether (PEGDME, M_w = 240) at (288.15–323.15) K for the purpose to understand SO₂–ether group interactions. Experimental bubble point pressures were lower than those expected from Raoult's law and showed strong interactions between SO₂ and functional ether group. Experimental data were correlated with Flory–Huggins and ASOG group contribution models. Only the two groups, SO₂ and –CH₂OCH₂–, and were considered in the ASOG model with the group pair interaction parameters being determined from data at the azeotropic point of the SO₂–dimethyl ether system. The ASOG group contribution model was found to be more reliable for calculation than the Flory–Huggins model and gave average relative deviations (ARDs) of 2.25% and 7.05% for the bubble point pressures of the SO₂–dimethyl ether and SO₂-1,4-dioxane systems, respectively. A steric factor, ({f}_{{-text{CH}_{2}}text{OCH}_{2}-}) = 0.589 for the –CH₂OCH₂– group in PEGDME allowed the ASOG model to calculate bubble point pressures with an ARD of 5.61% for the SO₂–PEGDME system. PEGDME and related polyethers can be considered as possible SO₂ gas capture solvents.

The kinetics of the reaction of 5-nitroisatin with morpholine in water–acetonitrile and water–methanol solvents was followed spectrophotometrically in the ranges of solvent composition (10–90% v/v) over the temperature range from 25 to 45 °C. The reaction was measured under pseudo-first-order condition respect to 5-nitroisatin and the overall reaction is second-order rate. The rate constant of reaction decreased with increasing organic solvent ratios and strongly increased with increasing water ratios in both mixed solvents. The thermodynamic activation parameters were calculated and explained. Both linearity and non-linearity were observed between log k_N and reciprocal dielectric constant for both solvents suggesting that the reaction of 5-nitroisatin with morpholine depends on specific as well as non-specific solvation of the medium. The reactivity was analyzed in the light of various single, dual, and multiple-regression equations using Kamlet–Taft solvatochromic parameters which were applied successfully to the mixed aqueous–acetonitrile and aqueous–methanol mixtures. Finally, a mechanism for the reaction is proposed.

The composition of coexisting phases for liquid-liquid and solid-liquid-liquid equilibria were measured at 298.2 and 313.2 K and under atmospheric pressure for the following systems: {sodium bromide + formamide + ethyl acetate}, {sodium thiocyanate + ethanol + (R)-limonene}, and {sodium thiocyanate + methanol + dibutyl ether}. These concentrations were determined mainly by chromatography and, for the first system, with the help of argentometric titration. The standard uncertainties in mole fractions varied between 0.001 and 0.008. The tie-line data were reproduced by the NRTL model with medium accuracy. Several empirical equations were used and tested to correlate binodal curves. The rational form of the equation, based on the liquid–liquid–solid tie-line, turned out to be the most adequate.

Various technological devices, from sensors to energy storage, water separators, and solar energy to fuel photocatalysts, use SnO₂, a multifunctional semiconductor ceramic. One of the important factors in the manufacture of semiconductor materials is the solvent, which influences the band gap value of the material. The objective of this study is to obtain SnO₂ semiconductor material with a band gap in visible light absorption through a simple precipitation method in terms of the impact of ethanol and methanol solvents. The ethanol and methanol solvent effects have band gap values ranging from 2.56 to 2.66 eV.

The activity and osmotic coefficients of electrolyte solutions are relatively scarce under super-ambient conditions. This study computes the activity and osmotic coefficients of aqueous lithium nitrate solutions to a molality of 7 mol·kg⁻¹, within the pressure range 0.1 to 60 MPa, and temperature range 298.15 K to 398.15 K. In particular, the pressure dependences of the activity and osmotic coefficients have been estimated with the equations derived by Rogers and Pitzer (J Phys Chem Ref Data 11:15–81, 1982) on the basis of the Pitzer ion-interaction approach using the literature apparent molar volume data. These pressure effects in conjunction with the low-pressure activity and osmotic coefficient data on aqueous lithium nitrate solutions provide estimates of the values of these coefficients under high pressures. Effects of temperature, pressure, and molality on the activity and osmotic coefficients have been discussed.

In previous articles (Partanen and Partanen in J. Chem. Eng. Data 65: 5226 − 5239 (2020), J. Solution Chem. 52: 1352 − 1385 (2023)), we presented a traceable and transparent three-parameter model for thermodynamic activity and enthalpy quantities in aqueous NaCl solutions. The model is based on extended Hückel equations with parameters B, b₁, and b₂ and it applies from T = 273.15 to 373.15 K up to the saturated solutions. These studies demonstrate that the model explains the literature data of almost all thermodynamic quantities including apparent and partial molar enthalpies within experimental error. In the model, the ion-size parameter in the Debye–Hückel equation, B, is regarded as a constant while the parameters of the coefficients of the linear and quadratic molality terms, b₁ and b₂, respectively, possess quadratic temperature dependences. In this study, the results obtained for the heat capacity quantities of NaCl(aq) are considered. We show that the available heat capacity literature for these solutions can be predicted at least satisfactorily up to the saturated solutions with our new model. Following this success, we supplement the existing thermodynamic tables with the new values for the relative apparent and partial molar heat capacities for NaCl solutions. It is likely that the new tables contain the most reliable values determined so far even though no calorimetric data were used in the parameter estimation of our model.

Graphical Abstract

The study aimed to investigate the properties of thermodynamics, acoustics, and electromagnetism in order to understand the interactions between molecules both within and between different compounds. The study also examined how molecular shape and structure, as well as temperature and the presence of chlorine atoms in alkanes and alkenes, influenced these properties. Measurements were taken for densities (ρ), speeds of sound (u), and refractive indices (({n}_{text{D}})) in various mixtures containing acetophenone with 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, trichloroethene or tetrachloroethene at temperatures ranging from 298.15 K to 318.15 K. Additionally, excess molar volumes (({V}_{text{m}}^{text{E}})), isentropic compressibilities(({K}_{s})), excess isentropic compressibilities (({kappa }_{text{S}}^{text{E}})), and excess refractive index ({(n}_{text{D}}^{text{E}}),) were calculated. The quantities were correlated with the Werblan relation. The ({V}_{text{m}}^{text{E}}) values exhibited negative for all mixtures except for acetophenone + 1,2-dichloroethane which had positive values while the tetrachloroethene system showed both positive and negative values. The (({kappa }_{text{S}}^{text{E}}),) values were showed negative for all binary mixtures. Lastly, (text{the} {(n}_{text{D}}^{text{E}})) values for acetophenone with 1,2-dichloroethane were negative and with tetrachloroethene an inversion in sign at low volume fraction of acetophenone was observed. For the three remaining binary mixtures the ({(n}_{text{D}}^{text{E}})) values were exhibited positive. The PC-SAFT model accurately predicted mixture densities and matched well with experimental data.

Although many models have been developed for solute partition coefficient (or solvation Gibbs free energy, ΔG_solv), how to develop models for rapid and accurate solvation energy predictions still remains challenging. In this work, a relation named the A-P scheme based on the Q–e scheme in radical copolymerizations and the Arrhenius equation for chemical kinetics is for the first time proposed to correlate the partition coefficients with supposed nonpolar and polar contributions from solute and solvent molecules. When compounds used as a solute or a solvent were allocated a parameter A denoting nonpolar contribution and another parameter P meaning polar contribution, the partition coefficients (or solvation Gibbs energies) of any solute/solvent pair can be calculated with the A-P scheme. Further, 6238 experimental solvation Gibbs energies were used to test the A-P scheme, resulting in a root means square (rms) error of 2.89 kJ·mol⁻¹, lower than the chemical accuracy of 4.18 kJ·mol⁻¹. Unlike other empirical approaches or quantitative structure–property relationship (QSPR) models, the proposed new scheme in this paper is not restricted to a specific solvent or solute and has markedly less computational intensity in predicting solute partition coefficient (or solvation Gibbs free energy). Therefore, the A-P scheme proposed in this work is feasible in rapid and accurate calculation of solvation Gibbs energies.

Graphical Abstract

This work is based on the investigation of thermophysical properties of pure ionic liquids {ILs; 1-ethyl-/1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; [EMIM][(NTf)₂], [BMIM][(NTf)₂], solvent acetonitrile (ACN), and its binary mixtures. Under these investigations, density (ρ) and ultrasonic velocity (u) were measured using high-precision vibrating-tube densitometer and viscosity (η) with an automated falling ball microviscometer for all components as functions of the mole fraction of ILs (({x}_{1})) at T = 298.15–323.15 K and p = 0.1 MPa. ρ, u, and η data of pure and binary components were used to evaluate excess/deviation parameters, and these parameters are correlated utilizing the extended form of Redlich–Kister equation. Interactions inside the ion pair of ILs and ILs–solvent are well discussed in terms of various specific/nonspecific forces of attractions. The interactions between the ion pair (({[text{EMIM}]}^{+})/(left[text {BMIM}right]^{+}) and ({left[{text{NTf}}_{2}right]}^{-})) as well as IL solvent was calculated using Density Functional Theory (DFT) in terms of various parameters at the D3-B3LYP/6–311 +  + G(d,p) level of theory. Moreover, various molecular properties, including structures, frontier molecular orbitals, electrostatic potentials, atomic charges, dipole moments, interaction energies, reactivity descriptors, zero-point energy (ZPE), and heat capacity, were obtained at the same level of theory. Thereafter, the natural bond orbital (NBO) analyses were performed to see all the interactions between donor–acceptor atoms at molecular level.

The reference interaction site model (RISM) theory has been employed in the study of hard homonuclear and heteronuclear diatomic liquids. The RISM equation coupled with the Percus–Yevick and Martynov–Sarkisov closures has been solved numerically. The excess chemical potential has been computed using analytic expression based on correlation functions. An improved prediction of an excess chemical potential has been done with an interpolation scheme, which relates an excess chemical potential for hard-sphere fluid to that of tangent hard-sphere diatomic fluid at the same density. Our findings for an excess chemical potential for hard homonuclear fluid are compared with available accurate data. Maximum deviations of the excess chemical potential from the Percus–Yevick and Martynov–Sarkisov approximations are of (9.56%) and of (5.58%), respectively. Some values of numerically obtained excess chemical potential for hard heteronuclear diatomic fluid present good comparison with available Monte Carlo data. To our knowledge, this is the first attempt to calculate an excess chemical potential for hard diatomic fluid in the Martynov–Sarkisov approximation. Moreover, radial distribution functions for hard-sphere, tangent hard homonuclear, and heteronuclear diatomic fluids from the Martynov-Sarkisov approximation are in good agreement with those in the literature.