Binary Solvent Mixtures Of Water Research Articles

Solvatochromism and preferential solvation of 2,6-dichloro-4-nitroaniline in pure and binary aqueous mixtures

In this study, the solvatochromic behavior of 2,6-dichloro para-nitroaniline (DCPNA) was investigated in a wide range of pure solvents, and binary solvent mixtures of water with ethanol, dimethyl sulfoxide, and dimethyl formamide at 298.15 K. The absorption spectrum of DCPNA in the ultraviolet–visible range exhibits a characteristic peak that shifts with changes in the solvent along the absorption wavelength. The influential factors and their roles in solvatochromism were determined through KAT-LSER analysis in pure solvents. Solvatochromism in binary solvent mixtures showed a completely non-linear trend with respect to the composition of the solution. The recently introduced preferential solvation model was utilized to model the absorbed light wavenumber in aqueous solvent mixtures. This model elucidates the separate effects of preferential solvation of DCPNA and the non-ideal behavior of aqueous solvent mixtures in the non-linearity of solvatochromism.

Determination and correlation of solubility and solution thermodynamics of β-HMX in binary solvent mixtures

Experimental solubility data of β-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (β-HMX) in three binary solvent mixtures of water + (acetic acid, acetone or DMSO) over the temperature ranges of (283.15–368.15 K) were measured with a gravimetric method under atmospheric pressure. The results all showed that the solubility of β-HMX monotonously decreases with the increase of water mole fraction except for that in mixture of water + acetic acid through all given temperatures investigated, which exhibited the trends reach maximum then descending according to the increase of water mole fraction. In the temperature ranges examined, it was found that the solubility of β-HMX in all the tested solvents increased with the rising of temperature. Furthermore, the experimental solubility data in binary solvents was correlated with the modified Apelblat equation, the CNIBS/R-K model and the Jouyban-Acree model, which all gave satisfactory results. Additionally, the mixing Gibbs free energy, enthalpy and entropy of β-HMX in those binary solvent systems were predicted with the correlation of experimental data on basis of the multicomponent NRTL model.

Some Aryl-1,2,4-triazol-1-ium Phenacylids in Binary Hydroxyl Solvent Mixtures. Computational and Spectral Study

Four carbanion monosubstituted p-aryl-1,2,4-triazol-1-ium methylids are subjected to a comparative study between their spectral and quantum-mechanical parameters in order to obtain more information about their structural features in hydroxyl solvents as water and ethanol and also on the nature of electronic absorption transitions from the visible range. The quantum mechanical analysis, made by the Spartan’14 program, established a series of molecular parameters of the studied ylids important for their reactivity and for intermolecular interactions with hydroxyl liquids. An extensive solvatochromic study of 1,2,4-triazol-1-ium ylids is impossible due to their limited solubility in liquids. Binary solvent mixtures of water and ethanol with known solvent parameters from the literature were used for this study. The electronic absorption spectra in binary solvents water and ethanol were used to establish the influence of intermolecular interactions on the spectral characteristics of the studied methylids and also on the composition of their first solvation shell in ternary solutions. The difference between the interaction energies in molecular pairs ylid–water and ylid–ethanol was determined based on the statistical cell model applied to the ternary solutions of the type of ylid + water + ethanol. The obtained values are very small due to the hydroxylic nature of the two solvents.

Solvatochromic Study of Two Carbanion Monosubstituted 4-Tolyl-1,2,4-triazol-1-ium Phenacylids in Binary Hydroxyl Solvent Mixtures

Two 4-tolyl-1,2,4-triazol-1-ium methylids, namely 4-tolyl-1,2,4-triazol-1-ium-phenacylid and 4-tolyl-1,2,4-triazol-1-ium-4′-nitro-phenacylid, are studied from solvatochromic point of view in binary solvent mixtures of water with ethanol and water with methanol. The contributions (expressed in percent) of the universal and specific interactions are separated from the spectral shifts recorded in the visible range for each composition of the binary solvent mixture. The essential role of the orientation and induction interactions in the studied solutions was demonstrated. Based on the statistic cell model of the binary solvent mixture solutions, the difference between the formation energies of ylid-water and ylid-alcohol complexes is estimated. The composition of the ylid’s first solvation shell was also established using the model of the binary solvent mixture solutions. The results obtained from the statistical cell model were compared with those obtained by using the Suppan’s model, resulting a good agreement.

Solid-liquid equilibrium solubility measurement, model evaluation and Hansen solubility parameter of 2,4,5-trimethoxybenzaldehyde in four aqueous binary solvent mixtures

The solid–liquid equilibrium solubility of 2,4,5-trimethoxybenzaldehyde (ANH) in four kinds of aqueous binary solvent mixtures (including water + acetone, water + acetonitrile, water + N, N-dimethylformamide and water + tetrahydrofuran) was determined with a temperature ranging from 278.15 K to 323.15 K under approximately 0.1 MPa. The solubility of ANH increases with the increase of temperature and the composition of good-solvent in all the tested binary solvent mixtures. The solubility of ANH is temperature-sensitive in the binary solvent mixture of water + THF system and solvent-sensitive in the binary solvent mixture of water + DMF. The Hansen solubility parameter for ANH and the selected solvents was employed to analyze the probabilities of miscibility between solute and solvents. Four thermodynamic models (i.e., the modified Jouyban-Acree model, the Sun model, the NRTL model, and the Wilson model) were selected to correlate the experimental data. The NRTL model fitted best among all the thermodynamic models with RAD and RMSD values are less than 0.0186 (water + acetone) and 0.000950 (water + THF), respectively. The solubility data are of guiding significance to the crystallization process of ANH.

Solubilities of Oleanolic Acid and Ursolic Acid in Different Organic Solvents and 2-Propanol + Water Binary Solvent Mixtures at Different Temperatures: Experimental Measurement and Modeling

The solubilities of oleanolic acid and ursolic acid in 1-butanol, methyl isobutyl ketone, methyl tert-butyl ether, and 2-propanol + water binary solvent systems at different temperatures were deter...

Further comments on “Experimental measurements, equilibrium study and model correlation of methyl paraben in ethanol and methanol aqueous solutions from = (293.15 to 323.15) K”

The experimental solubility data of methyl paraben in ethanol + water and methanol + water binary solvent mixtures at temperature range from (293.15 to 323.15) K have carefully been reanalyzed and some recommendations were proposed. In addition, preferential solvation analyses based on the inverse Kirkwood-Buff integrals show that this compound is preferentially solvated by water in water-rich mixtures in both binary systems but preferentially solvated by the cosolvent in the composition region of 0.24 < x1 < 1.00 for ethanol + water mixtures and the composition region of 0.31 < x1 < 1.0 for methanol + water mixtures.

Solubility Measurement and Correlation of Ceftiofur Sodium Trihydrate in Four Binary Solvent Mixtures

The solubility of ceftiofur sodium trihydrate (CST) in binary solvent mixtures of water + acetonitrile, water + ethanol, water + n-propanol, and water + iso-propanol at temperatures from 273.15 to 313.15 K (P = 0.1 MPa) was measured by a laser dynamic method. The experimental results show that the solubility is positively correlated with temperature. In the four binary solvent systems, the solubility value of CST initially increases first and then decreases with increasing organic solvent composition. The maximum solubility values occur in the molar content of organic solvent of about 0.5 for water + acetonitrile, 0.5 for water + ethanol, 0.4 for water + n-propanol, and 0.4 for water + iso-propanol. The accuracy of experimental results was examined by the Apelblat model, the Van’t-JA model, and the Apel-JA model, and the Apelblat model shows the best fitting performance.

Solubility determination and correlation for azithromycin monohydrate and dihydrate in solvent mixtures

The solubility of azithromycin monohydrate in binary solvent mixtures (ethanol + water and propanol + water) was studied by a static method with a temperature range from 283.15 K to 323.15 K under atmospheric pressure. Besides, azithromycin dihydrate in acetone + water binary solvent mixtures was reported with temperature ranging from 283.15 K to 323.15 K. Results showed that the solubility of azithromycin monohydrate and dihydrate in binary solvent mixtures all increased with temperature and the content of organic solvents. The solubility data in binary solvent mixtures were correlated by van't Hoff-Jouyban-Acree model, Apelblat-Jouyban-Acree model, Ma model and Sun model, and all models could be used to correlate the solubility of azithromycin monohydrate and dihydrate in the solvent mixtures. All the result mentioned in this study could help purify azithromycin monohydrate and dihydrate.

Self-Assembly of Monodispersed Carnosine Spherical Crystals in a Reverse Antisolvent Crystallization Process

Spherical crystallization is an effective way to increase particle size, raise bulk density, and improve flowability and compressibility of crystals with small sizes, especially needle-like and flake-like microcrystals. In this work, a reverse antisolvent crystallization method was used to obtain the spherical crystals of carnosine instead of commercially available needle-like carnosine material. Besides, the solubility of carnosine in a binary solvent mixture of water + ethanol was measured at temperatures ranging from 288.05 to 323.15 K by using a gravimetric method under atmospheric pressure to optimize this crystallization process and increase the yield of carnosine. On the basis of these thermodynamic data, single factor analysis in a reverse antisolvent crystallization process was performed, including carnosine aqueous solution concentration, feeding rate, volume ratio of solution to antisolvent, temperature, and stirring speed. Polarizing microscopy, particle size distributions, and in situ particl...

Phase evolution, structural characteristics and mechanism of vesicle formation from a synthetic amphiphile: Controlled morphology by tuning solution phase parameters

We report herein, the aggregation behavior of 3, 4-di(dodecyloxy)benzoic acid-4-hydroxy phenyl ester (DDBE), a synthetic amphiphile and a true non-ionic surfactant system as per the geometrical considerations. The true surfactant nature of the system stems from its hydrophilic-lipophilic-balance (HLB = 4.7), comparable to that of Span-60, also a true non-ionic surfactant. This compound undergoes spontaneous vesicle formation in THF:water binary solvent mixtures which further underwent fission at lower DDBE concentrations and fusion at higher concentrations, leading to giant vesicles of the order of 3000 nm. These vesicles are sensitive to the polarity of their environment. The predominant mode of interaction as observed from the molecular dynamics simulations were found to be π-π stacking with the phenyl rings of the molecule. Further, the system, upon complete extraction into water, formed spherical aggregates of size 50 nm based on the good solvent-poor solvent combination as the necessary condition for the vesicle formation.GRAPHICAL ABSTRACT

Molecular Interactions of 2-Naphthol in Binary Solvent Mixtures of Water+Methanol and Water+Ethanol with DFT Study

Molecular Interactions of 2-Naphthol in Binary Solvent Mixtures of Water+Methanol and Water+Ethanol with DFT Study

Molecular Interaction Study of Potassium Fluoride in Aqueous Lactose Solution at Different Temperatures

The present experimental investigation was carried out in order to explore the possible molecular interactions of potassium fluoride in aqueous lactose solution at different temperatures. Experimental values of density (ρ), viscosity (η) and ultrasonic velocities (U) were carried out on the liquid ternary mixtures of water + lactose + potassium fluoride. The binary solvent mixture of water, 5%, 10 %, and 15% of lactose was prepared under molality (m) basis. Potassium bromide was added under different molalities with these binary solvent mixtures. The related parameters correlated to our present study such as adiabatic compressibility, change and relative change in adiabatic compressibility, acoustic impedance, intermolecular free length, relative association, classical absorption coefficient, relaxation time were determined. The present investigation deals with the possible molecular interactions such as ion-ion, ion-solvent, solute-solvent, solute-solute which are identified and eventually discussed about the behavior of solute (potassium fluoride) in the solvent mixture.

Solubility and dissolution characteristics of capecitabine in pure lower alcohols and water with methanol mixture solvents at atmospheric pressure and different temperatures

Capecitabine is a widely used anticancer prodrug of 5-fluorouracil, but up to the present time there is no solubility data reported other than in supercritical carbon dioxide. In this paper, by the polythermal method, the solubility data of capecitabine in fifteen pure lower alcohols and water with methanol mixture solvents were measured from 278.15 K to 323.15 K under atmospheric pressure. The results show that the solubility of capecitabine in linear lower alcohols are bigger than that in corresponding branch chain lower alcohols, and decrease with the increasing of carbons in alkyl of alcohols. Moreover, the solubility of capecitabine increases with the increasing of temperature and mole fraction of methanol in the binary solvent mixtures of water + methanol. To expand industrial application of experimental solubility data of capecitabine in recrystallization, the values measured in selected pure lower alcohols are correlated using the modified Apelblat equation, the Buchowski-Ksiazczak-pletrzyk equation, the van't Hoff equation, the Wilson model and the NRTL model; And for the binary solvent system, the modified Apelblat equation and Jouyban-Acree model are used to correlate the solubility data. By evaluating the deviations between experimental and correlated data, all the correlated data by six models used in this research show comparable precision to those attained by careful experimental measurement. Moreover, some apparent thermodynamic quantities (ΔSdo, ΔHdo, ΔGdo, %ζH and %ζTS) of the dissolution processes of capecitabine in selected solvents and temperature range studied were calculated by the parametric van't Hoff equation. According to the calculation, the dissolution of capecitabine in lower alcohols and water with methanol mixture solvents is an endothermic and entropy-driven process. The solubility and apparent dissolution characteristics of capecitabine in this paper would provide basic support for industrial design and further studies.

Photophysical behavior of systematically substituted (di-2-pyridylaminomethyl) benzene ligands and its Re(I) complexes: A combined experimental and theoretical approach

Abstract The photophysical behavior of a series of flexible di-2-pyridylaminomethyl substituted ligands systematically substituted on a rigid benzene core and their corresponding mono-metallic Re(I) complexes have been investigated by steady state and time-resolved fluorescence spectroscopy in different composition of DMSO–water binary solvent mixtures. Unusual fluorescence properties in lower DMSO content ( X DMSO = 0.1–0.3) solvent mixtures is consistent with fascinating property of DMSO, which is known to perturb the hydrogen bonding ability of water with the solute. Spin allowed inter-ligand π–π * transition is more apparent in (1, 3) substituted systems. The calculated spectroscopic parameters of the complexes are significantly different from the ligands, mainly due to ligand to metal charge transfer. The experimental observations are in very good agreement with the theoretical results obtained at B3LYP/6-31G(d,p)/LANL2DZ level of density functional theory (DFT) calculation. Natural bond orbital (NBO) analysis and examination of frontier molecular orbitals reveal that the basic architecture of the symmetrically substituted multi-chromophoric ligand can induce excitation energy hopping, similar to an artificial antenna system.

Solubility and thermodynamic parameters of a novel anti-cancer drug (DHP-5) in polyethylene glycol 400 + water mixtures

Abstract Solubility of dihydropyrimidine derivative 4-(4-ethoxyphenyl)-5-(3,4,5 trimethoxybenzoyl)-3,4-dihydropyrimidine-2(1H) one (DHP-5), a novel anticancer drug, was experimentally measured in PEG-400 + water binary solvent mixtures over a temperatures range from 298.15 to 318.15 K. Thermodynamic parameters including enthalpy, entropy and Gibbs free energy of the solubility data were calculated using van't Hoff equation. Experimental solubility data was employed to evaluate the relative performance of a number of models including van't Hoff, Apelblat, Yalkowsky and Jouyban–Acree models for their prediction efficacy. The Jouyban–Acree model covering both solvent composition and temperature effects on drug's solubility proved to be superior to the other three models for its prediction accuracy.

Solubility and preferential solvation of phenacetin in methanol + water mixtures at 298.15 K

ABSTRACTThe mole fraction solubility of phenacetin (PNC) in methanol + water binary solvent mixtures at 298.15 K was determined along with density of the saturated solutions. All these solubility values were correlated with the Jouyban–Acree model. Preferential solvation parameters of PNC by methanol (δx1,3) were derived from their thermodynamic solution properties using the inverse Kirkwood–Buff integrals (IKBI) method. δx1,3 values are negative in water-rich mixtures but positive in methanol mole fraction of >0.32. It is conjecturable that in the former case the hydrophobic hydration around non-polar groups of PNC plays a relevant role in the solvation. The higher solvation by methanol in mixtures of similar cosolvent compositions and methanol-rich mixtures could be explained in terms of the higher basic behaviour of methanol.

The electrospinning behavior of poly(vinyl alcohol) in DMSO–water binary solvent mixtures

The fiber diameters obtained from PVA–DMSO–water ternary system are the result of the interplay between the solvent–solvent and solvent–polymer interactions.

Preferential Solvation of Ketoprofen in Some Co-solvent Binary Mixtures

The preferential solvation parameters of ketoprofen (KTP) in ethanol (EtOH) + water and propylene glycol (PG) + water binary solvent mixtures were obtained from their thermodynamic properties by means of the inverse Kirkwood–Buff integrals (IKBI) and quasi-lattice quasi-chemical methods. According to the IKBI method, it is found that KTP is very sensitive to specific solvation effects, so the preferential solvation parameter by co-solvents, δx 1,3, is negative in the water-rich mixtures of both binary systems but positive in the other compositions at temperatures of 293.15, 303.15 and 313.15 K. From this it can be assumed that, in water-rich mixtures, hydrophobic hydration around the aromatic rings and the methyl group, present in the drug, plays a relevant role in the solvation. The bigger amount of drug solvation by the co-solvent in mixtures of similar solvent proportions and in co-solvent-rich mixtures could be due mainly to polarity effects. Moreover, in these mixtures the solute will be acting as a Lewis acid with the co-solvent molecules, because they are more basic than water.

Protonation Constants of Uridine 5′-Monophosphate in Different Aqueous Solutions of Methanol

The protonation equilibria of uridine 5′-monophosphate disodium salt (UMP) was determined in binary solvent mixtures of water–methanol containing 0, 10, 15, 20, 25, 30, 35, 40, 45, and 50 % (v/v) methanol, using a combination of spectrophotometric and potentiometric methods at 25 °C and constant ionic strength (0.1 mol·dm−3 NaClO4). The protonation constants were analyzed using Kamlet, Abboud, and Taft parameters. A good linear correlation of the protonation constants (on the logarithmic scale) was obtained. Dual-parameter correlation of log10K versus π* (dipolarity/polarizability) and α (hydrogen-bond donor acidity), as well as π* and β (hydrogen-bond acceptor basicity), gave good results in various aqueous solutions of methanol. Finally, the results are compared with CMP, a homolog of UMP, and are discussed in terms of the effect of the solvent on the protonation constants.