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The solid - liquid equilibrium solubility of β -Alanine in three different binary solvent mixtures, including (methanol + water), (ethanol + water) and (DMF + water), was measured by a gravimetric method at temperatures ranging from 288.15 K to 323.15 K. It is found that the solubility of β -Alanine is positively correlated with temperatures at a given solvent composition and negatively correlated with the molar fraction of organic solvents. The solid - liquid equilibrium data of β -Alanine was fitted by the modified Apelblat equation, CNIBS/R-K equation and NRTL model. It turned out that all the selected thermodynamic models could give satisfactory results. Moreover, the apparent thermodynamic properties of the dissolution process, including the standard Gibbs free energy, enthalpy, and entropy were calculated based on the van't Hoff analysis. The corresponding results indicate that these dissolving processes of β -Alanine in the selected solvents are endothermic and entropy-driving. [ABSTRACT FROM AUTHOR]

The solubility of calcium d -pantothenate in (water + methanol) mixtures and the effect of β -alanine on the solubility of calcium d -pantothenate in a constant mole ratio of methanol and water was measured from 263.15 K to 303.15 K by the HPLC analysis method ( P = 0.1 MPa). The solubility of calcium d -pantothenate increased with increasing temperature in all the mixtures at constant composition. Besides, it also increased with mole fraction of water in (water + methanol) mixtures at a constant temperature. Additionally, the solubility of calcium d -pantothenate was enhanced by β -alanine at a given temperature. The experimental solubility in (water + methanol) mixtures was correlated by the modified Apelblat equation, the ternary NRTL equation and Solubility-Polarity Model. The Apelblat equation, the quaternary NRTL equation and the Cohn equation were adopted to correlate the experimental solubility in the (water + methanol + β -alanine) mixtures. Worthwhile, the quaternary NRTL equation was first applied to correlating the quaternary solid-liquid equilibrium. It turned out that all the selected models give good performance on solubility prediction. [ABSTRACT FROM AUTHOR]

Those comments from Acree on “Effect of β -alanine and the solvent composition on the solubility of solvate of calcium d -pantothenate containing four molecules of methanol and one molecule of water ( d -PC·4MeOH·1H 2 O)” are very valuable and helpful for improving the quality of our paper. Here according to the comments, we make a deep analysis and discussion of our article again. Firstly, we need to make a restatement that S 0 and S actually represent the solubility with no impurity in the solution and the solubility in the solution containing impurity in our article, respectively. Secondly, the experimental solubility was reanalysed by the new Cohen equation suggested by Acree Jr, and the results show that the original Cohen equation could give the better agreement. Finally, the modified Solubility-Polarity equation was adopted to correlate the solubility in terms of the relative dielectric constant. [ABSTRACT FROM AUTHOR]

• Solubility of p -Acetamidobenzoic acid in 12 pure solvents was determined. • Experimental solubility was correlated by the modified Apelblat equation, the λh model and the NRTL model. • The melting point of p -Acetamidobenzoic acid was estimated by the group contribution method. • Sigma profiles and solvation free energy were computed on the basis of COSMO-RS model. The solubility of p -Acetamidobenzoic acid (PAABA) in 12 pure organic solvents was measured using the gravimetric method in the temperature range of 283.15 K to 323.15 K. It was discovered that the solubility curves in different solvents cross each other when the temperature increased. Besides, the modified Apelblat equation, the λh model and the NRTL model were used to fit the measured solubility data of PAABA and the modified Apelblat equation and λh model gave the minor deviation compared with the NRTL model. The underlying mechanism between PAABA and solvent molecules was revealed in light of physical properties, sigma profiles and solvation free energy analysis, based on COSMO-RS model. The results indicated that the solubility of PAABA in most alcohol solvents are related to the value of solvation free energy. These data are helpful to further study the crystallization process of PAABA. [ABSTRACT FROM AUTHOR]

• Solubility of KFM in five mono-solvents and three binary solvents was determined. • KFM solubility was correlated with the modified Apelblat, λh equation, and van't Hoff equation. • Statistical method was used to analyze impact of physicochemical parameters of solvents on solubility of KFM. • The COSMO-RS model was used to explore effects of solvent-solute interactions on solubility of KFM. The solubility of kaempferol monohydrate (KFM) in five mono-solvents (ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol) and three binary solvents (ethanol + water, 1-propanol + water, 2-propanol + water) was measured by gravimetric method from 283.15 K to 323.15 K at the pressure of 0.1 MPa. It is concluded that solubility of KFM is a function of temperature and solvent composition. Statistical method was used to analyze the impact of physicochemical parameters of solvents on solubility of KFM, indicating that comprehensive factors, such as the hydrogen bonding donor capacity and cohesive energy density would influence on solubility of KFM. In addition, the COSMO-RS model was used to explore the effects of solvent-solute interactions on solubility of KFM. Further, the solubility data was correlated by the modified Apelblat equation, λh equation, and van't Hoff equation, in which the modified Apelblat equation showed the best correlation result. In the final, the apparent thermodynamic properties ( Δ sol H 0 , Δ sol G 0 , Δ sol S 0) of KFM were derived through the van't Hoff equation, demonstrating the dissolution process of KFM in the selected solvents was endothermic. We hope the solubility of KFM determined in this work provides data can support for its further purification. Solubility of kaempferol monohydrate (KFM) in five mono-solvents and three binary solvents was measured and correlated. Statistical method was used to analyze the impact of physicochemical parameters of solvents on the solubility of KFM, and the COSMO-RS model was used to explore the effects of solvent-solute interactions on solubility of KFM. Also, the apparent thermodynamic properties of KFM were derived through the van't Hoff equation. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, the solubility of L-histidine in three different binary solvents, including (water + acetone), (water + ethanol) and (water + 2-propanol), was measured over temperatures from 283.15 K to 318.15 K by employing a gravimetric method at atmospheric pressure. It was found that the solubility of L-histidine in the binary mixed solvents increases with the increasing temperature at a given solvent composition, whereas it decreases with the rise of mole fraction of organic solvents. The experimental results were well correlated by the modified Apelblat equation, CNIBS/R-K model, combined version of the Jouyban-Acree model and NRTL model, respectively. This shows that these models can correlate the solubility in three binary mixed solvents accurately. Furthermore, the mixing thermodynamic properties of L-histidine in different binary solvent mixtures were also calculated based on the NRTL model. The result indicates that the mixing process of L-histidine is endothermic and spontaneous. [ABSTRACT FROM AUTHOR]

The solubility of Avermectin B 1a (AVM B 1a ) in the three binary solvent mixtures, (acetone + water), (acetone + n-hexane) and (isopropanol + n-hexane) was determined gravimetrically with the temperature ranging from 283.15 K to 313.15 K under atmospheric conditions. The experimental results indicate that the solubility of AVM B 1a increased with increasing temperature at certain solvent composition, and decreased with increasing mole fraction of water and n-hexane. Besides, the modified Apelblat equation, CNIBS/R-K model and Jouyban-Acree model were employed to correlate the solubility results obtained. All the selected models provide satisfactory results. Furthermore, the mixing thermodynamic properties were calculated based on the NRTL equation, a binary activity coefficient model. We also calculated the thermodynamic properties of the dissolution process of AVM B 1a . The calculated results indicate that the dissolution process of AVM B 1a in the tested solvents is endothermic and spontaneous. [ABSTRACT FROM AUTHOR]

Solubility of 3MBA in fourteen mono-solvents was determined by gravimetric method and correlated by the modified Apelblat model, λ h model, van't Hoff model and NRTL model. The influence of different solvent property parameters on solubility was analyzed qualitatively and quantitatively. The calculated topological index (H) was used to explain the dissolution behavior firstly. COSMO-RS model was used to calculate the σ -profile and solvation free energy to reveal solubility trend in molecular level. [Display omitted] • Solubility of 3MBA in fourteen mono-solvents was determined and correlated. • The influence of different solvent property parameters on solubility was analyzed qualitatively and quantitatively. • The calculated topological index (H) was used to explain the dissolution behavior firstly. • COSMO-RS model was used to calculate the σ -profile and solvation free energy to reveal solubility trend in molecular level. A gravimetric method was used to determine the equilibrium solubility of 3-methoxybenzoic acid (3MBA) in 14 kinds of organic mono-solvents (methanol, ethanol, n-propanol, iso -propanol, n-butanol, iso -butanol, sec -butanol, formic acid, acetic acid, ethyl formate, methyl acetate, ethyl acetate, iso -propyl acetate, butyl acetate) from 278.15 K to 323.15 K at 0.1 MPa. In all the solvent systems studied, the solubility increases monotonously with the increasing of temperature. In addition, the effect of solvent properties on solid–liquid equilibrium of 3MBA was investigated. The results show that dissolving process of 3MBA in solvent is a complex process, which is affected by the action of solvent properties; Correlation analysis found that the solvent properties containing hydrogen bond donation (α), hydrogen bond acceptance (β), polarity index (E T 30 ), Hildebrand solubility parameter (δ H), cohesive energy density and surface tension process great influence on the dissolving behavior of 3MBA. And then, topological index (H) which can reflect the molecular structure information of the solvents was calculated. It was found that the solubility of 3MBA decreased with the increasing of H values in alcohol and ester solvents, and increased with the increasing of H values in carboxylic acid solvents. Besides, the solubility of 3MBA were related to the modified Apelblat model, λ h model, van't Hoff model and NRTL model, and the modified Apelblat model gave the best correlation results, with the ARD % of 0.68%. In addition, COSMO-RS model was used to calculate the σ -profiles and solvation free energy of selected solute–solvent systems, σ -profiles analysis was qualitatively described the intermolecular interaction, it was found that the solubility of 3MBA in the selected solvents was correlated with the solute–solvent intermolecular interactions; Solvation free energy was calculated in the "Molar" framework and found that the solubility of 3MBA in alcohols, esters and carboxylic acids decreased with the decreasing of the absolute value of the solvation free energy. [ABSTRACT FROM AUTHOR]

Solubility of benzoin in three binary solvent systems of acetone + ethanol, acetone + 1-butanol, acetone + 1-propanol was measured by static analytical method ranging from 283.15 K to 318.15 K at atmospheric pressure. Density functional theory (DFT) and molecular dynamic (MD) simulation were employed to investigate relationship between solute and solvent molecules. According to results of Solvation free energy and hydrogen bond strength, the solubility of benzoin increases with increasing value of hydrogen bond strength. Radial distribution function (RDF) resulted shows that ethanol, 1-butanol, 1-propanol have an effect on the acetone aggregation in binary mixed solvents, which means it will weaken the interactions between benzoin and acetone molecules. Therefore, solubility behavior was influenced by both solute-solvent and solvent-solvent interactions. The solubility data was correlated with Apelblat equation, CNIBS/R-K equation, and λh model, respectively, and the CNIBS/R-K equation shows the best correlations in three thermodynamic equations. Thermodynamic properties of mixing enthalpy, entropy, and Gibbs energy were further estimated and their implication on dissolution process of benzoin was discussed. [ABSTRACT FROM AUTHOR]

The solid-liquid equilibrium (SLE) of l -norvaline in three different binary solvents, including water + methanol, water + ethanol and water + 2-propanol, was determined by employing a gravimetric method over temperatures from 283.15 K to 318.15 K. It is found that the equilibrium solubility of l -norvaline in the mixed solvents increases with rising temperature at constant solvent composition and decreases with the increasing molar fraction of organic solvents. Moreover, the dissolving capacity of l -norvaline in the three binary solvent mixtures at constant temperature can be ranked as (methanol + water > ethanol + water > 2-propanol + water) in general. Furthermore, a model which can be called polar equation was applied to quantitatively describe the relationship between solubility and polarity of solvent mixtures. The results demonstrate that the increasing polarity of the binary solvents can enhance the solubility of l -norvaline. Besides, the experimental solubility was well correlated by the modified Apelblat equation, λh equation, and NRTL model, with the maximum ARD % values: 1.89%, 3.48%, and 6.42%, respectively. Additionally, the mixing thermodynamic properties of l -norvaline in three binary solvent mixtures were also discussed based on the NRTL model. Results show that the mixing processes of l -norvaline are endothermic and spontaneous. [ABSTRACT FROM AUTHOR]

The solubility of boscalid in five pure solvents, including methanol, ethanol, isopropanol, ethyl acetate and n-propyl acetate, and two binary solvent mixtures, including (ethanol + ethyl acetate) and (isopropanol + ethyl acetate), was determined by a gravimetric method with temperatures ranging from (288.15 to 313.15) K. It turns out that the solubility of boscalid increases with the increasing of temperature in all selected solvents. Moreover, it is interesting that the solubility of boscalid in the two binary solvent mixtures performed a maximum effect with the decreasing mole fraction of ethyl acetate at a given temperature. The solubility of boscalid in pure solvents was correlated by the modified Apelblat model and λh model while that in binary solvent mixtures was correlated by the modified Apelblat model, CNIBS/R-K model and Jouyban-Acree model. It is found that all the models could give satisfactory correlation results with less than 3% of all the ARD values. Furthermore, the thermodynamic properties of the mixing processes in all solvents selected were calculated and discussed based on the NRTL model. [ABSTRACT FROM AUTHOR]

Solubility behavior of d -mannitol ( d -man) in pure water and four water-organic solvents from 288.15 K to 318.15 K at atmospheric pressure was studied by both phase equilibria and molecular modelling methods. A dynamic method was employed to determine the data on equilibrium, both molecular dynamic (MD) simulations and density functional theory (DFT) calculations were carried out to uncover the relationship between intermolecular interactions and solubility behavior. The MD results illustrate that the strength in hydrogen bond of solute-organic solvent captures the solubility ranking of d -man in corresponding mixed solvents, and the radial distribution function (RDF) plots indicate that organic solvents have enhancement effect on the water aggregation in solution which weakened the strong interaction between d -man and water molecules. Both of them suggest that solubility behavior not only depends on solute-solvent interaction, the solvent-solvent interaction also plays a key role in determining it. The solubility was further fitted by the modified Apelblat model, λh model, NRTL model and finally, mixing properties (enthalpy, Gibbs energy and entropy) were discussed, indicating the dissolution process is governed by both enthalpy and entropy of solution. [ABSTRACT FROM AUTHOR]

In this work, a UV spectroscopic method was used to determine the solubility of troxerutin in eleven mono-solvents and (1,4-dioxane + 2-propanol) mixtures at different temperatures from 288.15 K to 323.15 K. The solubility of troxerutin was positively correlated with temperature in all selected solvents, and it showed a maximum value when the mole fraction of 2-propanol was 0.4 in binary solvent mixtures. The modified Apelblat equation, λh equation, CNIB/R-K model, NRTL model and Jouyban-Acree model were used to correlate the solubility data of troxerutin. It turned out that all the selected thermodynamic models could fit the results well, especially for the modified Apelblat equation with all the ARD values are less than 2%. Furthermore, the thermodynamic properties of troxerutin in different pure and binary solvents were also calculated and are discussed. The results indicated that the dissolution process of troxerutin in the experimental solvents was endothermic. Through analysis of enthalpy-entropy compensation in (1,4-dioxane + 2-propanol) mixtures, a non-linear Δ d H o versus Δ d H o plot was obtained, indicating that the driving mechanism changes with the proportion of 2-propanol in the dissolution process of troxerutin. [ABSTRACT FROM AUTHOR]

The solubility of cefmetazole acid in binary solvent mixtures, (methanol + water), (ethanol + water) and (isopropanol + water), was determined by UV spectroscopic method at temperatures from 278.15 to 303.15 K. The solubility of cefmetazole acid increased with the increase of temperature in all solvents. In (methanol + water) co-solvent mixture, the solubility of cefmetazole acid is maximal in neat methanol. In (ethanol + water) and (isopropanol + water) solvent mixtures, the solubility of cefmetazole acid reaches its maximum when the mole fraction of alcohol is 0.5 and 0.4, respectively. The modified Apelblat equation, the CNIBS/R-K model and the Jouyban–Acree model were applied to correlate the experimental solubility of cefmetazole acid. Moreover, the activity coefficients as well as the thermodynamic properties of mixing were calculated and discussed based on the NRTL model and experimental solubility values. [ABSTRACT FROM AUTHOR]

A laser monitoring dynamic method was used to determine the solubility of 4-aminobutyric acid in five mono-solvents of methanol, formamide, 1,2-propanediol, 1,3-propanediol and water, and (methanol + water) binary solvent mixtures over the temperature ranging from 283.15 K to 323.15 K at atmospheric pressure. It turns out to be that in different mono-solvents, the solubility of 4-aminobutyric acid is temperature dependent and increases with the increasing temperature. While in (methanol + water) binary solvent mixtures, the solubility is positively correlated with temperature and negatively correlated with the mole fraction of methanol. The modified Apelblat equation, λh equation and NRTL_Binary model were employed to correlate the solubility data in five mono-solvents. While in (methanol + water) binary solvent mixtures, the NRTL_Ternary model, CNIBS/R-K model and Jouyban-Acree models were applied. It is found that the correlated results are in good agreement with the experimental results. Furthermore, with the activity coefficients considered, solution mixing thermodynamics were calculated and the dissolution process of 4-aminobutyric acid is also discussed. [ABSTRACT FROM AUTHOR]

The solubility of pyridoxine hydrochloride in binary solvent mixtures, including (acetone + water), (methanol + water) and (ethanol + water), was measured over temperature range from (278.15 to 313.15) K by a gravimetric method at atmospheric pressure ( P = 0.1 MPa). The solubility increased with increasing temperature in binary solvent mixtures at constant solvent composition. Besides, the dissolving capacity of pyridoxine hydrochloride in the three binary solvent mixtures at constant temperature ranked as (methanol + water > ethanol + water > acetone + water) in general, partly depending on the polarity of the solvents. Additionally, the modified Apelblat equation, van’t Hoff equation, CNIBS/R–K model and Jouyban–Acree model were used to correlate the solubility data in binary mixtures, it turned out that all the selected thermodynamic models could give satisfactory results. Furthermore, the mixing thermodynamic properties of pyridoxine hydrochloride in different binary solvent mixtures were also calculated and discussed. The results indicate that the mixing process of pyridoxine hydrochloride in the selected solvents is exothermic. [ABSTRACT FROM AUTHOR]