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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]

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]

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]

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]

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]

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]