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Glucosamine hydrochloride (GAH) is a kind of natural hexose, which is used to promote the synthesis of mucopolysaccharides and improve the metabolism of articular cartilage. In this paper, the solubility of GAH in pure water and aqueous system with the presence of three kinds of additives (HCl, NaCl, KCl) at temperatures ranging from 278.15 K to 323.15 K was determined by gravimetric method. When there are additives in water, the solubility of GAH increases with the increase of temperature and decreases with the increase of concentration of the three kinds of additives. When the additives were at similar mole fractions, HCl led to the lowest solubility of GAH. The modified Apelblat model and van't Hoff model were used to correlate the solubility data. The average relative deviation (ARD) data of Apelblat and van't Hoff models were less than 5%, indicating good fitting results. Based on the thermodynamic data, the cooling crystallization process of GAH was performed. It was found that the additives could affect the crystal morphology, particle size, and yield of GAH products. This study supplemented the thermodynamic data of GAH and studied the cooling crystallization process in the presence of GAH additives, which provided important guidance for the optimization of the crystallization process. [ABSTRACT FROM AUTHOR]

• Solubility of GAH in four binary solvents were determined and correlated. • The dissolution thermodynamic properties were calculated. • Hirshfeld surface analysis was performed to investigate molecular interactions within crystals. • The intermolecular interactions in solution were revealed by MD simulation and RDF analysis. Glucosamine hydrochloride (GAH) is a marine biological preparation derived from natural chitin and improves articular cartilage metabolism. In this study, the solubility of GAH in four binary solvents (water + methanol, water + ethanol, water + isopropanol, and water + acetone) was gravimetrically determined over the temperature range of 283.15 K to 323.15 K. The solubility of GAH were found increasing monotonically with water content and temperature. In alcohol mixtures, the solubility of GAH can be ranked as: (water + methanol) > (water + ethanol) > (water + isopropanol). Four thermodynamic models (the modified Apelblat equation, van't Hoff equation, (CNIBS)/R-K model and Jouyban-Acree model) were used to correlate the experimental solubility data, which the (CNIBS)/R-K model showed the best fitting performance. The dissolution thermodynamic properties of GAH were also calculated. The results indicate that the dissolution process is driven by both entropy and enthalpy. To explore the solid–liquid equilibrium behavior from molecular level, the Hirshfeld surface of GAH crystal was generated and molecular dynamics simulations of mixed systems were performed. Based on equilibrium configurations of different mixtures, molecular interactions between solvent–solvent and solute–solvent were calculated. Meanwhile, the simulation snapshots and radial distribution function plots were analyzed to interpret association of solvents. [ABSTRACT FROM AUTHOR]

Solubility of gabapentin anhydrate/monohydrate in alcohol-water mixtures was experimentally determined. An interesting trend of the solubility was found, which showed both maximum and minimum solubility with different solvent compositions at one temperature. Molecular dynamics simulations were carried out to explore the effect of solvent composition on the solubility, indicating that the water association played an important role. Critical water activity and the transition temperature of gabapentin anhydrate/hydrate were also determined, and a relationship between them was established to investigate the factors influencing the hydration. Furthermore, the ternary phase diagram of (gabapentin-ethanol-water) at 293.15 K was built by slurry experiments for further understanding of the crystal form transformation, which confirmed the stability regions of anhydrate/monohydrate and verified the above established relations. Then the dehydration/hydration process in the solution can be predicted and controlled, thus obtaining the desired product. [ABSTRACT FROM AUTHOR]

The solubility of pyraclostrobin in five pure solvents and two binary solvent mixtures was measured from 283.15 K to 308.15 K using a static analytical method. Solubility in five pure solvents was well correlated by the modified Apelblat equation and Wilson model. While the CNIBS/R–K model was applied to correlate the solubility in two binary solvent mixtures, the correlation showed good agreement with experimental results. The solubility of pyraclostrobin reaches its maximum value at a certain cyclohexane mole fraction in the two binary solvent mixtures. The solubility parameter of pyraclostrobin was calculated by the Fedors method and a new modified mixing rule with preferable applicability was proposed to determine the solubility parameter of solvents. Then the co-solvency in the binary solvent mixtures can be explained based on the obtained solubility parameters. In a addition, the dissolution thermodynamic properties were calculated from the experimental values using the Wilson model. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a static analysis method to experimentally determine the (solid + liquid) equilibrium of racemic oxiracetam in (methanol + water), (ethanol + water) and (isopropanol + water) binary solvents with alcohol mole fraction ranging from 0.30 to 0.90 at atmosphere pressure ( p = 0.1 MPa). For the experiments, the temperatures range from (283.15 to 308.15) K. The results showed that the solubility of oxiracetam increased with the increasing temperature, while decreased with the increasing organic solvent fraction in all three tested binary solvent systems. The modified Apelblat model, the CNIBS/Redlich–Kister model, the combined version of Jouyban–Acree model and the NRTL model were employed to correlate the measured solubility values, respectively. Additionally, some of the thermodynamic properties which can help to evaluate its dissolution behavior were obtained based on the NRTL model. [ABSTRACT FROM AUTHOR]

The solubility of diphenhydramine hydrochloride (DH) in four pure solvents (methanol, ethanol, acetone and ethyl acetate) and two binary solvents (ethanol + ethyl acetate) and (ethanol + acetone) was determined at temperatures from (278.15 to 323.15) K. The experimental solubility of DH is well correlated by the modified Apelblat equation, the CNIBS/R-K equation and the hybrid model, respectively. All the measured solubility of DH shows temperature dependence. In binary mixtures, the solubility curve displays a maximum with the solvent composition changing, particularly, the maximum point increases with temperature. Moreover, the activity coefficients as well as thermodynamic properties of mixing were obtained and discussed. [ABSTRACT FROM AUTHOR]

• Solubility of dicyandiamide in three kinds of binary solvent mixtures were determined and correlated. • Thermodynamic properties of mixing were calculated based on the NRTL equation. • Polarity of liquids were discussed. The reason for the high solubility of dicyandiamide in N,N-dimethylformamide was discussed. Dicyandiamide (DCD) is an important chemical raw material. The solid–liquid equilibrium solubility of DCD in three kinds of binary solvent mixtures (N,N-dimethylformamide (DMF) + ethanol, DMF + acetonitrile, DMF + acetone) at T = (283.15–323.15) K was determined by gravimetric method. The thermodynamic parameters of DCD dissolution in solvents were studied. The solubility of DCD in the three groups of binary mixed solvents increases with the increase of temperature. In three binary mixed solvents, the solubility of DCD increases monotonically with the increase of DMF composition. The modified Apelblat model, van't Hoff model, λh model, the nonrandom two-liquid (NRTL) model and the Apelblat-Jouyban-Acree model were used to correlate the solubility data. The results show that the modified Apelblat model have the best correlation with the solubility of DCD. The calculation of thermodynamic parameters during the dissolution process indicates that dissolution is exothermic and driven by both enthalpy and entropy. This work can provide reference for improving the crystallization process of DCD, as well as for improving the chemical production process using DCD as raw material. [ABSTRACT FROM AUTHOR]

The structure and properties of Dimethyl sulfone (DMSO 2) were investigated in both solid state and solution phase. In particular, the effect of four categories of solvent properties including hydrogen bonding donor and acceptor propensity, solvent polarity and cohesive energy density on solid-liquid phase equilibrium of DMSO 2 were examined in detail. The intermolecular interactions derived from Hirshfeld surface analysis demonstrate that the C H⋯O interactions are dominant in crystal packing of DMSO 2. The equilibrium solubility of DMSO 2 was then determined in twelve monosolvents including water, straight and branch chain lower alcohols, and esters using gravimetrical method in the temperature ranging from 283.15 to 323.15 K. As expected, the solubility data is positively correlated with temperature, and DMSO 2 bears the highest solubility in methyl acetate among all studied solvents. Further, it was found that the solubility of DMSO 2 shows good correlation with cohesive energy density or the polarity of solvents except for the two lower alcohols of branch chain. The latter is likely due to other factors of solvent molecule involved such as steric hindrance, shape and size. Finally, the experimental data were well fitted by four thermodynamic models, and the modified Apelblat equation achieves the best fitting performance. • The equilibrium solubility of Dimethyl sulfone was measured using gravimetrical method in twelve monosolvents. • The effect of solvent properties on solid-liquid phase equilibrium of Dimethyl sulfone was investigated. • The intermolecular interactions of Dimethyl sulfone crystal were derived from Hirshfeld surface analysis. • The solubility behavior basically follows the rule of "like dissolves like". [ABSTRACT FROM AUTHOR]

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 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]

In this work, the solubility of allisartan isoproxil in binary solvent mixtures, including (acetone + water), (acetonitrile + water) and (methanol + water), was determined by a gravimetric method with the temperature ranging from (278.15 to 313.15) K at atmospheric pressure ( p = 0.1 MPa). The solubility of allisartan isoproxil in three binary solvent mixtures all increased with the rising of temperature at a constant solvent composition. For the binary solvent mixtures of (methanol + water), the solubility increased with the increasing of methanol fraction, while it appeared maximum value at a certain solvent composition in the other two binary solvent mixtures (acetone + water and acetonitrile + water). Based on the theory of solubility parameter, Fedors method and two mixing rules were employed to calculate the solubility parameters, by which the proximity of solubility parameters between allisartan isoproxil and binary solvent mixtures explained the co-solvent phenomenon. Additionally, the modified Apelblat equation, CNIBS/R-K model and Jouyban-Acree model were used to correlate the solubility data in binary solvent mixtures, and it turned out that all the three correlation models could give a satisfactory result. Furthermore, the mixing thermodynamic properties were calculated based on NRTL model, which indicated that the mixing process was spontaneous and exothermic. [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 solid-liquid equilibrium data of eszopiclone in six pure organic solvents and two binary mixed systems was determined by employing a gravimetric method under atmospheric pressure at temperatures ranging from 288.15 K to 328.15 K. For each selected solvent, the solubility data of eszopiclone increases with increasing temperature. It was found that composition of mixed solvents has a significant influence on the solubility of eszopiclone, that there exhibits a synergistic effect at some certain composition points for both mixed systems. Experimental solubilities were fitted by different models including the modified Apelblat equation, λh model, CNIBS/R-K model and the Hybrid model, the calculated results were found to agree well with the experimental data. At last, the van't Hoff equation was employed to calculate the thermodynamic parameters of all selected solutions, corresponding results confirm that these dissolving processes are endothermic and entropy-driving. [ABSTRACT FROM AUTHOR]

The solubility of penicillin V potassium(PVK) in binary ethanol+ water and 1-butyl alcohol + water solvent mixtures was measuredat temperatures ranging from (278.15 to 313.15) K. The solubilityin ethanol + water was measured by a static analytical method whilein 1-butyl alcohol + water a dynamic method was adopted. It was foundthat the solubility of PVK increased with increasing temperature aswell as the increase of the initial mole fraction of water. The modifiedApelblat equation, the CNIBS/R-K equation, the combined version ofthe Jouyban-Acree and van’t Hoff model, and the hybrid modelwere used to correlate the solubility data in ethanol + water solventmixtures, among which the CNIBS/R-K equation gave the best correlationresults. The experimental solubility data in 1-butyl alcohol + waterwere correlated well by the van’t Hoff equation and the modifiedApelblat equation. The dissolution enthalpy, entropy, and Gibbs energyof PVK in these solvent mixtures were obtained based on the van’tHoff equation. [ABSTRACT FROM AUTHOR]

• Solubility of ropivacaine in fourteen pure solvents were determined and correlated. • Thermodynamic properties of mixing were calculated based on the NRTL equation. • Polarity, cohesive energy density and dielectric constant of liquids were discussed. • The molecular structure of ropivacaine were studied by HS and MEPs analysis. • The intermolecular interactions were revealed by MD simulation and RDF analysis. The solubility of ropivacaine in fourteen pure solvents at 283.15 K to 323.15 K was determined via the gravimetric method and was well correlated with three thermodynamic models, including the Apelblat, λh , and NRTL models. Among all experimental solvents, the solubility of ropivacaine was found to be highest in pure THF and lowest in acetonitrile. In alcohol solvents, the maximum solubility was observed in amyl alcohol followed by 1-butanol, while the minimum value was observed in 1-propanol. The thermodynamic properties of mixing were calculated based on the NRTL equation, indicating that the mixing processes are spontaneous and entropy-driven. In addition, the crystal structure of ropivacaine was obtained and investigated by Hirshfeld surface analysis and molecular electrostatic potential surface analysis. The physicochemical properties of solvents, such as polarity, cohesive energy density and dielectric constant, were analyzed to explain the solid–liquid behavior of ropivacaine. Finally, a molecular dynamics simulation and radial distribution function analysis were performed. The results indicated that ropivacaine could interact with organic solvents via van der Waals interactions, electrostatic interactions, and hydrogen bonding. [ABSTRACT FROM AUTHOR]

• The solubility of valsartan (form E) was determined and correlated. • The mixing thermodynamic properties of crystal form E were calculated. • Hirshfeld surface and molecular electrostatic potential analyzed close contacts. • The intermolecular interactions were explored by molecular dynamics simulation. Valsartan is an angiotensin II receptor antagonist used to treat hypertension. Crystals of valsartan were prepared and the stability of the valsartan (form E) at different solvents and temperatures was investigated. The solid-liquid equilibrium solubility of valsartan (form E) in twelve pure solvents was determined by a dynamic method at the temperature from 278.15 K to 323.15 K. Among the solvents used in the experiment, the solubility of valsartan (form E) was found to be highest in methanol and lowest in acetonitrile. In straight-chain alcohols, the solubility decreases with the increase of carbon chain length. The modified Apelblat model, λh model and NRTL model were used to correlate the solubility data. The thermodynamic properties of the mixing process such as Gibbs free energy, enthalpy and entropy were estimated by applying the NRTL model. The KAT-LSER model was adopted to explore solvent effects. Hirshfeld surface analysis and molecular electrostatic potential (ESP) were employed to visualize close contacts and charge distribution of valsartan and solvents. In addition, molecular dynamics (MD) simulation was performed to calculate intermolecular interactions between solute and solvent. Radial distribution function (RDF) and the mean square displacement (MSD) analyses were also carried out to explore molecular association and molecular diffusion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solubility data of clozapine in eighteen pure organic solvents were determined. • Different thermodynamic models were used to correlate solubility data. • Solubility increase with the increasing of temperature. • Dissolution properties of clozapine were calculated based on the Wilson model. The solid-liquid equilibrium solubility of clozapine in eighteen organic solvents (i.e. , methanol, ethanol, n -propanol, i -propanol, n -butanol, i -butanol, s -butanol, n -pentanol, i -pentanol, acetone, 2-butanone, acetonitrile, N , N -dimethylformamide, tetrahydrofuran, chloroform, ethyl formate, methyl acetate, and ethyl acetate) was determined using a gravimetric method over a temperature ranging from 278.15 K to 323.15 K at atmospheric pressure. The modified Apelblat equation, λh equation, NRTL equation, and Wilson equation were selected to correlate the solubility data. The fitting degree of thermodynamic models was evaluated by the relative average deviation, and root mean root mean square deviation. Dissolution properties, including enthalpy, entropy, and Gibbs energy changes of clozapine were evaluated by the Wilson model. The solubility data, thermodynamic parameters and dissolution properties for clozapine will be of crucial guiding value for the optimization of the industrial crystallization process. [ABSTRACT FROM AUTHOR]

In this work, we determined the solubility of imazapyr in twelve mono organic solvents by gravimetric method over the temperature ranging from 283.15 K to 323.15 K at atmospheric pressure, and the results show that the equilibrium solubility is positively correlated with temperature in all solvents. Meanwhile, Hirshfeld surface analysis and molecular electrostatic potential surface were severally employed to probe into the intermolecular interactions and the overall charge distribution of imazapyr, the estimated results indicate that H···H and O···H contacts obviously predominate among all contact interactions and imazapyr has great hydrogen bonding donor and acceptor capacities. Besides, we investigated the effects of physicochemical properties of solvents on dissolution behaviors and found that solvent polarity plays a decisive role in the solubility of imazapyr in most cases. Molecular dynamic (MD) simulations were further applied to interpret the solute-solvent interactions behind different solubility behaviors of imazapyr. Additionally, the experimental solubility values were well correlated by the modified Apelblat equation, λh equation as well as NRTL model, respectively. And all of the ARD% values are less than 3%, indicating that the three thermodynamic models all achieve the perfect fitting performance. Finally, the mixing thermodynamic properties including ∆ mix G 0, ∆ mix H 0, and ∆ mix S 0 were calculated based on the NRTL model. The results suggest that the mixing process is spontaneous, exothermic and entropy driven as well. The solubility of imazapyr is positively correlated with temperature. Molecular Hirshfeld surface analysis indicates that the H···H and O┄H contacts prominently dominate among all contact interactions and MEPs analysis suggests that imazapyr holds great hydrogen bonding donor/acceptor capacities, indicating that strong hydrogen bonding interactions can be formed between imazapyr and polar solvents. RDF analysis further reveals that hydrogen bonding interactions is the decisive factor for the highest solubility of imazapyr in methanol. [Display omitted] • Solubility of imazapyr was measured by gravimetric method in twelve pure organic solvents. • Molecular dynamic simulations were used to probe into the interaction of solute-solvent. • Three thermodynamic models were provided to correlate the solubility of imazapyr. [ABSTRACT FROM AUTHOR]

The cyhalothric acid (CTA), an important intermediate for the production of pyrethroids, was selected to obtain its solubility data in eleven pure solvents using gravimetric method from 283.15 K to 323.15 K. Among the alcohol solvents, methanol with the largest polarity has the lowest solubility and tert-butanol has the strongest solubility. Three ester solvents have similar solvency to CTA. The physicochemical properties of solvents and radial distribution function (RDF) analysis based on molecular dynamic (MD) simulation were further employed to interpret the difference of solubility. Moreover, the experimental solubility of CTA in pure solvents was well correlated by modified Apelblat equation, λh equation and the NRTL (nonrandom two-liquid) model, respectively, in which the modified Apelblat equation achieved the best fitting. The mixing properties (enthalpy, Gibbs energy and entropy) were also determined and the results show that mixing process is spontaneous and entropy-driven. • The solubility of cyhalothric acid (CTA) was measured. • Molecular dynamic simulation was used to probe the interaction of solute-solvent. • Three thermodynamic models were used to correlate the solubility of CTA. [ABSTRACT FROM AUTHOR]

Solubility of vitamin B6 hydrochloride (VB6H) in three water-organic binary mixed solvents from 278.15 K to 313.15 K at atmospheric pressure was investigated by experiments and molecular simulations. The solvation free energy suggests that the solubility of VB6H increases with solute-solvent interaction strength increasing and there exists the strongest interaction energy at co-solvency composition in binary solvents. Radial distribution function (RDF) shows the tendency to aggregation of two solvent molecules as the molar fraction of organic solvent in mixtures increases, which suggests, to some extent, the interaction between solute and solvent molecules would be weaken and the solubility of VB6H decreases. It could be concluded that the solubility behavior of VB6H is a result from both solute-solvent and solvent-solvent interactions. Then the experimental data were correlated by the modified Apelblat model, the λh model, the CNIBS/R–K model and the NRTL model, respectively. And all of the models present a good consistency with the data. Furthermore, the calculations of mixing thermodynamic properties show that the mixing process of VB6H in the investigated solvents is exothermic and spontaneous. The experimental data can be used as basic data in the industrial production and scientific research of VB6H, a high value-added product. MD simulations and correlation models herein are helpful to understanding of solid-liquid equilibrium of compounds in binary solvent systems, then prediction of solubility which is the target of considerable researches. • Solubility of vitamin B6 hydrochloride was measured by static method in three mixtures. • Solute-solvent and solvent-solvent interactions were investigated by solvation free energy and RDF. • The co-solvency behavior of VB6H was a result from both solute-solvent and solvent-solvent interactions. • Thermodynamic properties were analyzed by mixing functions. [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 mole fraction solubility of tetrabromobisphenol A in nine pure solvents and two binary solvents was determined using the gravimetric method. Different thermodynamic models were employed to analyze the dissolution behavior of tetrabromobisphenol A in pure and binary solvents. In addition, the analysis of the thermodynamic properties implies that the lower mixing Gibbs free energy is, the stronger interaction between solute and solvent is, leading to higher solubility. [ABSTRACT FROM AUTHOR]

Solid-liquid phase equilibrium solubility of prothioconazole in seven mono-solvents and (2-propanol ± cyclohexane, 1-butanol ± cyclohexane) binary solvent mixtures was determined by gravimetric method from 283.15 K to 313.15 K at atmospheric pressure. The solubility of prothioconazole increased with increasing temperature in all tested solvents. In mono-solvents, the solubility values at a fixed temperature ranked as: 1-butanol > 1-propanol > 2-propanol > methanol > 2-butanol > acetonitrile > toluene. In binary solvent systems, the maximum solubility values were achieved at a certain solvent composition. The Apelblat equation, λh equation and NRTL model were employed to correlate the solubility data in mono-solvents, and the Apelblat equation in two binary solvent mixtures. The selected thermodynamic models can all give acceptable results. Furthermore, the apparent standard Gibbs free energy, enthalpy and entropy for the dissolution of prothioconazole were calculated, which indicates that the dissolution process of prothioconazole is an endothermic and entropy favorable process. [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]

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]

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 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]

The solubility of flunixin meglumine (FM) in six pure solvents and binary solvents of ethanol + isopropanol was measured over the temperature ranged from 283.15 K to 328.15 K by using a static gravimetric method. It is positively correlated with temperature and negatively correlated with the molar fraction of isopropanol. The modified Apelblat equation was used to correlate the experimental solubility in pure solvents. Dissolution properties based on the modified Apelblat equation were calculated and discussed. The solubility in binary solvents at various temperatures was well correlated by the nearly ideal binary solvent (NIBS)/Redlich–Kister model. In addition, in order to correlate the solubility to both the composition and temperature in mixed solvents, a new model related to dielectric constant was proposed. [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]

The solubility of thiamine nitrate in water + ethanol binary solvent mixtures and aqueous solution with different pH values was determined at temperatures from 278.15 K to 303.15 K by a laser monitoring observation technique at atmospheric pressure. The experimental solubility in water + ethanol system was correlated by the modified Apelblat equation and the CNIBS/R-K model, which both agree well with the experimental results. The dissolution enthalpy, entropy and Gibbs energy of thiamine nitrate were obtained by the van’t Hoff equation. The obtained results indicate that the dissolution process of thiamine nitrate is endothermic and entropy-driven. To evaluate the effect of pH value on the solubility of thiamine nitrate in aqueous solution, the Henderson–Hasselbalch (HH) equation was adopted to correlate the experimental solubility and the pH value. It is found that the experimental solubility precisely follows the HH equation and the pH value has a big impact on the solubility of thiamine nitrate at a given temperature. Besides, in this work, to account for the combined effect of pH value and temperature on the solubility of thiamine nitrate in aqueous solution, a modified equation based on the HH equation was established for the first time, and it shows a good correlation between the experimental data and the calculated results. [ABSTRACT FROM AUTHOR]

Thesolubility of ibuprofen sodium dihydrate (ISD) in acetone +water mixtures was measured by the gravimetric method at temperaturesranging from (279.55 to 312.05) K. The measured solubilities werecorrelated by the modified Apelblat equation, the λh(Buchowski) equation, the van’t Hoff model, the combinednearly ideal binary solvent/Redlich–Kister (CNIBS/R-K) equation,and the general single model. The modified Apelblat equation was thebest model for correlating the solubility of ISD, while the generalsingle model fits the best for mixed solvents. The standard enthalpy,entropy, and Gibbs energy of the dissociation process of ISD werecalculated by the van’t Hoff equation and the modified Apelblatmodel. In addition, there was a maximum value of solubility at a certainacetone mole fraction in the acetone + water mixture. [ABSTRACT FROM AUTHOR]

The solid-liquid phase equilibrium solubility of clozapine in six of aqueous binary solvent mixtures (i.e., water + methanol, water + ethanol, water + n -propanol, water + acetone, water + N , N -dimethylformamide, and water + tetrahydrofuran) was determined from 278.15 K to 323.15 K at approximately 101.3 kPa with a gravimetric method. The solubility increases with the increase of temperature and the composition of good-solvent in all the selected binary solvent mixture systems. Polarity is an essential factor affecting the solubility of clozapine in mixed solvents. Hansen solubility parameters were used to analyse the solubility behaviour. Four thermodynamic models, including the CNIBS/R-K model, the modified Jouyban-Acree model, the NRTL model, and the Wilson model were chosen to fit the experimental solubility data. Relative average deviation, and root mean square deviation were employed to evaluate the fitting degree of each thermodynamic model. NRTL model fits best with the maximum RAD and RMSD value of 0.0177 (water + methanol) and 0.000847 (water + THF), respectively. Solubility data are the basis for calculation of supersolubility and induction time of the crystallization process. The basic solubility data play an important role in the process optimization of clozapine crystallization. [Display omitted] • Solubility data of clozapine in six kinds of aqueous binary solvent mixtures were determined. • The solubility increases with the increase of temperature and the composition of good-solvent. • Hansen solubility parameters were used to analyse the solubility behaviour. • Polarity is an essential factor affecting the solubility of clozapine in mixed solvents. [ABSTRACT FROM AUTHOR]

The solubility of Dimethylaminomicheliolide Fumarate Salt(referred to as DFS) in three binary solvent mixtures, including 1,4-dioxane + n-hexane, 1,4-dioxane + cyclohexane, 1,4-dioxane + n-heptane and three pure solvents 1,4-dioxane, acetonitrile and methyl isobutyl ketone, was determined by the gravimetric method at temperatures ranging from 288.15 K to 328.15 K at atmospheric pressure. With the increase of temperature, the solubility of DFS in the six solvent systems increases gradually. As the proportion of the anti-solvent increases, the solubility of the DFS gradually decreases in the three binary solvents systems. Apelblat model and NRTL model were used to analyze the solubility of DFS in the binary solvent mixtures, at the same time, the data in the pure solvents were analyzed with the Apelblat model and the λh model, respectively. The simulation results show good coherence to the correlation and reliability of the data because all ARD% are below 7%. Furthemore, the simulation results also prove that the entire mixing of hypothetical liquids process in the investigated solvents is spontaneous and exothermic. • The solubility of DFS increases with temperature in six solvent systems. • The experimental data was well correlated by the Apelblat, λh and NRTL models. • Thermodynamic analyses were performed based on functions of mixing. [ABSTRACT FROM AUTHOR]