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The latest developments of industrial crystallization in China are reviewed. This includes the introduction of representative scientists and institutions promoting the progress of Chinese industrial crystallization. Additionally, primary application fields related to industrial crystallization are outlined to give an overview of the current research trends in China. National and international industrial crystallization meetings held in China are also presented. Finally, the expectations for the future research activities in the field of industrial crystallization in China are briefly described. [ABSTRACT FROM AUTHOR]

Abstract: The solubility of candesartan cilexetil (Form I) was measured by a gravimetric method in aqueous solvent mixtures (ethanol–water, acetonitrile–water and acetone–water), and the calculated values by (NIBS)/Redlich–Kister equation agreed well with the experimental data. The relationship between solubility of candesartan cilexetil (Form I) and molar fraction of organic solvents (ethanol, acetonitrile and acetone) shown unimodal curves, and this phenomenon can be explained by ΔH sol–ΔG sol compensation theory. For ethanol–water and acetonitrile–water mixture, the plot of ΔH sol–ΔG sol compensation was nonlinear with positive and negative slopes, indicating that the increases of solubility were controlled by two different mechanisms (entropy and enthalpy). However, for acetone–water mixture, the plot of ΔH sol–ΔG sol compensation was a linear curve, indicating that enthalpy is the dominant mechanism to control the solubility enhancement. These results can also be used to explain that acetone molecule played an important role in increasing the solute–solvent interactions of the candesartan cilexetil (Form I). [Copyright &y& Elsevier]

• The solubility of MBZ in different mono-solvents was measured. • Molecular simulations were used to explain the dissolution behavior of MBZ. • The thermodynamic models were employed to correlate the solubility data of MBZ. • The mixing thermodynamic properties of MBZ in twelve mono-solvents were calculated by the NRTL equation. In this study, metronidazole benzoate (MBZ), a nitroimidazole antibiotic, was selected to measure the solubility in 12 solvents by the gravimetric method in the temperature range of 278.15 K to 323.15 K. The intermolecular interactions dominated by H···H and O···H contacts in the solid phase were determined using Hirshfeld surface analysis (HS). Subsequently, molecular simulations involving molecular electrostatic potential surface (MEPs), hydrogen binding energy (E HB) and mean square displacement (MSD) revealed the effect of the solvent polarity, hydrogen bonding and diffusion process on the dissolution behavior of MBZ. Furthermore, six thermodynamic models, all with values of ARDs less than 5 %, were successfully correlated with the experimental solubility results. The Apelblat model achieved the best fitting. Based on the NRTL models, relevant thermodynamic parameters were obtained, indicating that the dissolution process of MBZ in various solvents is spontaneous and entropy-driven. In the measured temperature range, the solubility of MBZ in different solvents increased from 4-times to 25-times as the temperature changed, which provided an important theoretical basis for the industrial production of MBZ. [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]

Nitroguanidine (NQ) is a commonly used explosive, which has been widely used for both civilian and military explosive applications. However, the weak flowability and mechanical performance limit its application. In this work, mechanical performance and thermodynamic stability of NQ crystals were improved by controlling crystal morphologies in the crystallization process. Typical NQ crystals with multiple morphologies and single crystal form were obtained in the presence of additives during the cooling crystallization. The morphology controlled NQ crystals showed higher density, unimodal crystal size distribution and enhanced flowability. The additives showed the inhibitory effect on the nucleation of NQ crystals by in-situ FBRM and PVM determination, and the mechanism was analyzed by means of morphological prediction and molecular simulation. Furthermore, the morphology controlled NQ crystals suggested higher thermodynamic stability according to the calculation of entropy, enthalpy, Gibbs free energy and apparent activation energy on the basis of DSC results. [ABSTRACT FROM AUTHOR]

In this work, the solubility of 2-Mercaptomethyl Benzimidazole (MMB)in eight pure solvents (i.e., ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, ethyl acetate, acetonitrile and acetone) and two binary solvents (ethanol + ethyl acetate and 1-butanol + acetonitrile) were measured by a dynamic method at a temperature ranging from (283.15 to 328.15) K at atmospheric pressure. For the temperature range investigated, the solubility of MMB in all solvents increased with increasing temperature. The solubility in the pure solvents was well-correlated with the Apelblat equation, λh equation and NRTL equation. Further, RK model, together with Apelblat equation λh equation and NRTL equation were employed to correlate the solubility in binary solvents. Besides, the thermodynamic data in both pure and binary solvents (i.e., Gibbs energy, enthalpy, and entropy of mixing) were calculated by using the NRTL model to rank the solubility values in different pure 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 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]

The solubility of pyrazinamide in ten solvents (water, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, acetone, acetonitrile and ethyl acetate) at temperatures ranging from (278.15 to 323.15) K was determined by using the gravimetric method. The experimental results indicated that in different solvents, the solubility of pyrazinamide was temperature dependent and increased with the increasing temperature. Besides, the modified Apelblat equation, λ h equation, Wilson model and NRTL model were employed to correlate the solubility data in the solvents. The results show that the correlated data are in good agreement with the experimental solubility. Furthermore, the mixing thermodynamic properties of pyrazinamide in different solvents were calculated based on the Wilson model. The outcome indicates that the mixing process of pyrazinamide is endothermic. [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]

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 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 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 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]

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]

In this work, the solubility of 1,3-dimethylurea form I (DMUI) in seven solvents including water, 2-butanol, 2-propanol, acetone, acetonitrile, ethyl acetate and butyl acetate were measured by a synthetic method at a temperature range from (288.15 to 328.15) K at atmospheric pressure. For the temperature range investigated, the solubility of DMUI in the selected solvents increased with increasing temperature. Results of these measurements were well-correlated with the modified Apelblat equation, λh equation, van’t Hoff equation and Wilson model. Besides, the thermodynamic data ( i.e. , Gibbs energy, enthalpy, and entropy of mixing) were calculated by using the Wilson model. The chemical potential, solvation free energy and interaction enthalpy of DMU in solution were calculated by COSMO-RS model. This model was also applied to predict DMU solubility which showed good agreement with the experimental values. [ABSTRACT FROM AUTHOR]

The solubility of l -methionine in three different binary mixed solvents of water + (methanol, ethanol, acetone) were experimentally measured by gravimetric method from T = (283.15 to 313.15) K ( P = 0.1 MPa). The experimental data indicate that the solubility of l -methionine in the binary mixed solvents increases with the increasing temperature and decreases with the rise of molar concentration of organic solvents. The modified Apelblat model, the λh model and the CNIBS/R–K model were used to correlate the experimental data, and all of the models provided good fitting to the data. Furthermore, the mixing thermodynamic properties of l -methionine in different binary solvent mixtures were also calculated and discussed. The results indicate that the mixing process of l -methionine in the investigated solvents is endothermic and spontaneous. The experimental solubility and correlation equations can be used as essential data and simulation models in the purification and separation of l -methionine. [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 data of thiourea in methanol + ethanol mixtures and methanol + n-propanol mixtures were determined from T = (283.15 to 313.15) K by gravimetric method under atmospheric pressure. Effects of solvent composition and temperature on solubility of thiourea were discussed. Molecular simulation results indicate that solubility of thiourea will be influenced by interaction energy and a quantitative conclusion can be drawn from the modeling result. To extend the applicability of the solubility data, experimental solubility data in two kinds of binary solvent mixtures were correlated by the modified Apelblat equation, λ – h equation and (NIBS)/Redlich–Kister model. It was found that all the three models could satisfactorily correlate the experimental data and the (NIBS)/Redlich–Kister model could give better correlation results. Furthermore, thermodynamic properties of dissolving and mixing process of thiourea, including the enthalpy, the Gibbs energy and the entropy, were also calculated and analyzed. [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]

The solubility data of simvastatin in five pure solvents and binary solvent mixtures of isobutyl acetate and n -heptane were experimentally determined by a gravimetrical method under atmospheric pressure. It was found that the solubility of simvastatin increases with temperature rising in all investigated solvents. In binary solvent mixtures, the solubility of simvastatin increases with the decreasing of the mole fraction of n -heptane. The Solubility–Polarity model was modified and used to interpret the dissolution behaviors of simvastatin in binary solvent mixtures. The experimental solubility data in all investigated solvents were correlated by empirical models with the relative average deviation percentage between experimental and calculated solubility less than 5%. The thermodynamic properties of simvastatin, including the Gibbs energy change, the entropy and the enthalpy of dissolution process, were also calculated. The results indicate that the dissolution process of simvastatin is a spontaneous, endothermic and entropy-driving process in all solvent systems. [ABSTRACT FROM AUTHOR]

By the gravimetric method, the solubility of sorbic acid in eight solvents including ethanol, 2-propanol, methanol, 1-butanol, ethyl acetate, methyl tert-butyl ether, acetone and acetonitrile was determined over a temperature range from 285.15 to K at atmospheric pressure. For the temperature range investigated, the solubility of sorbic acid in the solvents increased with increasing temperature. The experimental values were correlated with the linear solvation energy relationship, modified Apelblat equation, λh equation, non-random two-liquid (NRTL) model, and Wilson model. On the other hand, the enthalpy, entropy and Gibbs free energy of dissolution were obtained from these solubility values by using the van’t Hoff and Gibbs equations. The excess enthalpy of solution was estimated on the basis of λh equation. Furthermore, the a priori predictive model COSMO-RS was employed to predict the solubility of sorbic acid in selected solvents and reasonable agreement with experimental values is achieved. [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]

Solvent screening plays a key rolein the optimization of the drugcrystallization process based on the solubility data and dissolutionthermodynamic data. In this article, the solubility of cefixime trihydratein ethanol, propan-2-ol, butan-1-ol, butan-2-ol, pentan-1-ol, ethylacetate, and acetone from 278.15 to 323.15 K at atmospheric pressureis reported. It is found that the solubility of cefixime trihydratein all seven solvents increases with temperature. The modified Apelblatequation fits well with the experimental solubility data in all selectedsolvents with the average percent deviation less than 3.5 %. The mixingproperties including the mixing free Gibbs energy, enthalpy, and entropyof cefixime trihydrate were calculated based on the van’t Hoffequation. The results indicate that the dissolution process of cefiximetrihydrate in all tested solvents is endothermic, entropically drivenand not spontaneous. [ABSTRACT FROM AUTHOR]

The solubilities of ginsenoside compound K in pure solventsandbinary mixture solvents were determined at several temperatures from278.15 K to 318.15 K by a static analytical method. The experimentalsolubility data in pure solvents were correlated by the van’tHoff plot, the modified Apelblat equation, the λh(Buchowski) equation, the Wilson model, and the NRTL model, withthe Wilson model giving the best correlation results. Based on theWilson model and experimental data, the mixing Gibbs free energies,enthalpies, and entropies of solutions and activity coefficients inpure solvents were predicted, and other thermodynamic properties (infinite-dilutionactivity coefficients and excess enthalpies) were calculated as well.In addition, the solubility was maximal at a certain water mole fractionin acetone + water mixture and acetonitrile + water mixture, whereasin a methanol + water system, the solubility decreases as the waterconcentration increases monotonically. The solubilities in mixturesolvents were correlated by the solvent components using the Wilsonmodel. The partial molar Gibbs free energies with negative valueswere obtained, which indicates the changing of the solubility. [ABSTRACT FROM AUTHOR]