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• Solubility of isophthalic acid (IPA) in four different binary solvent systems was determined. • The experimental data was correlated with four thermodynamic models. • Molecular electrostatic potential surface (MEPS) and Hirshfeld surface (HS) analysis were used to investigate the intermolecular interactions. • The dissolution of isophthalic acid (IPA) was a non-spontaneous, endothermic and entropy-driven process. The solubility of isophthalic acid (IPA) in four different binary solvent systems (water + methanol, water + ethanol, water + 1-propanol, and water + isopropanol) was measured by the gravimetric method at atmospheric pressure from 283.15 K to 323.15 K. Under certain solvent compositions, the solubility of IPA increased with increasing temperature. The trend of solubility under isothermal conditions setting differs as the mole fraction of organic solvent increases. The solubility of IPA in water + methanol and water + ethanol systems increased with the mole fraction of methanol or ethanol. In the system of water + 1-propanol and water + isopropanol, as the mole fraction of organic solvent increased, the solubility of IPA increased firstly and then decreased gradually. The Hansen solubility parameters of IPA and selected solvents were analyzed, the analysis showed that the miscibility of IPA with the selected solvent was the result of many factors. Molecular electrostatic potential surface (MEPS) and Hirshfeld surface (HS) analysis were used to investigate the intermolecular interactions. The solubility data were correlated using the Apelblat equation, van't Hoff equation, λh equation, and Jouyban–Acree model. Besides, the vant Hoff equation was employed to analyze the apparent thermodynamic properties of dissolving process including the Gibbs energy, enthalpy and entropy. All positive values indicated that the dissolving process of IPA was non-spontaneous, endothermic, and entropy-driven. [ABSTRACT FROM AUTHOR]

In the presented work, a study on the solubility and intermolecular interactions of l -serine and L-cysteine was carried out in binary mixtures of H 2 O + dimethylformamide (DMF), H 2 O + dimethylsulfoxide (DMSO), and H 2 O + acetonitrile (ACN) in the temperature range of T = 288.15 K to 308.15 K. l -serine exhibited the highest solubility in water, while L-cysteine was more soluble in water-DMF. The solvation process was assessed through standard Gibbs energy calculations, indicating the solvation stability order: water-ACN > water-DMSO > water-DMF for l -serine, and water-DMF > water-DMSO > water-ACN for L-cysteine. This study also explored the influence of these amino acids on solvent–solvent interactions, revealing changes in chemical entropies and self-association patterns within the binary solvent mixtures. Variation of solubility of L-cysteine in Water-DMF in various mole fraction concentrations of DMF (X DMF) with temperature (K). [Display omitted] • l-serine shows highest solubility in water, generally decreasing with organic components, except water-ACN solvent system. • L-cysteine is more soluble in water-DMF, solubility order: water-DMF > water-DMSO > water-ACN. • Standard Gibbs energy calculations reveal l -serine's stability: most in water-DMSO, least in water-ACN. • Non-covalent interactions govern stability, l -serine's solvation most affected by DMF, while L-cysteine by ACN. [ABSTRACT FROM AUTHOR]

• The solubility of four compounds was investigated. • The differences in solubility of two organoaluminium compounds with different configurations were compared. • The experimental solubility data were correlated by different thermodynamic models. • Hirshfeld surface analysis and molecular electrostatic potential were used to explain the solvation behaviour of the compounds. Pyridinyl Schiff base ligands and their supporting organoaluminium compounds have diverse applications in catalysis, medicine, and electrochemistry. In this study, solubility data for two ligands (L1 = 2-(OH)C 6 H 4 CH = N(C 5 H 4 N), L2 = 2-(OH)-5-ClC 6 H 3 CH = N(C 5 H 4 N)) and two organoaluminium compounds (C1 = [2-O-C 6 H 4 CH = NC 5 H 4 N)]AlMe 2 , C2 = [2-O, 4-ClC 6 H 3 CHMeN(C 5 H 4 N)] 2 Al 2 Me 2) with differing configurations were obtained through static analysis. The data showed that at 298.15 K, for L1 , the solubility (102x) order was: toluene (42.339) > ether (23.085) > ethanol (5.025) ≥ methanol (4.888); for L2 , it was: tetrahydrofuran (7.348) > dichloromethane (4.289) > toluene (3.387) > ether (1.210); and for C1 and C2 , the order remained consistent as tetrahydrofuran (C1 :9.192, C2 :13.911) > toluene(C1 :2.904, C2 :6.036) > ether(C1 :2.254, C2 :4.358) > n -hexane(C1 :0.783, C2 :0.975). Subsequently, the solubility data were subjected to fitting using various thermodynamic models. The experimental findings revealed that the majority of the models exhibited good fits, with an average absolute relative deviation (ARD) of < 4 % and an average root mean square deviation (RMSD) of < 0.2 %. Notably, the Wilson model emerged as the most suitable for predicting the solubility of L1 , while the Polynomial model demonstrated superior efficacy in predicting the solubility of L2 , C1 , and C2. In the case of the organic aluminium compound C2 with a distinct configuration, the formation of a dimerized dinuclear metal structure resulted in altered polarity, consequently influencing solubility in various solvents. Molecular electrostatic potential analysis revealed electron densities at the O atom, the NH moiety of the pyridine ring, and proximal regions of the metal atoms, indicative of electronegativity and facilitation of hydrogen bonding. Hirshfeld surface analysis underscored H···H contact as the predominant interaction among the four compounds. Additionally, calculations regarding the apparent thermodynamic functions of L1 and L2 revealed an endothermic dissolution process characterized by increased entropy and driven by enthalpy. These experimental findings provide valuable insights into the properties of pyridinyl Schiff base ligands and their associated organic aluminum compounds, revealing complex relationships among molecular structure, solubility, and thermodynamic properties. They offer valuable clues for further research and application in this field. [ABSTRACT FROM AUTHOR]

This research provides a thorough investigation into the solubility behavior and solution thermodynamics of l-threonine in significant organic solvent systems. The work was done on measuring the actual solubility and subsequently calculating overall transfer solvation free energetics (∆ G energetic 0 i) and transfer entropies (∆ S t 0 i) at a temperature of 298.15 K. These measurements were performed as l-threonine transitioned from water to different water-organic mixed solvents systems. The saturated solubilities of l-threonine were determined using the 'gravimetric method' at five equidistant temperatures namely 288.15 K, 293.15 K, 298.15 K, 303.15 K and 308.15 K. By analyzing the data on solubility, we further obtained the different energies involved in solvation related issues. In the case of single solvents, the nature of solubility of l-threonine was observed like: dimethylsulfoxide (DMSO) < acetonitrile (ACN) < N, N -dimethylformamide (DMF) < ethylene glycol (EG) < water (H 2 O), irrespective of the experimental conditions. Specifically, at 298.15 K, the solubilities of l-threonine in single solvents were found to be as follows: 0.8220 mol per kg of water, 0.3101 mol per kg of EG, 0.1337 mol per kg of DMF, 0.1107 mol per kg DMSO and 0.1188 mol per kg of ACN. This research critically examines the relationship between the experimental saturated solubility of l-threonine and the complex properties influencing its solvation energy in diverse aqueous organic solvent systems. [Display omitted] • Solubility of l-threonine in various cosolvent systems and temperatures: EG-water > DMF-water > ACN-water > DMSO-water. • L-threonine's hydrophilic nature influences its solubility and interactions in water-EG/DMF/DMSO/ACN binary solvent systems. • Solvent molecule dimerization and their relative stabilities impact interactions, as seen in obtained values. • The study provides valuable insights for further scientific research in this area. [ABSTRACT FROM AUTHOR]

• Equilibrium solubilities of GuHCl in different binary solvents were investigated. • The molecule interactions of solvent-solvent and solute-solvent were researched through molecular dynamics simulation. • Five thermodynamic models were utilized to regress the observed solubility data. • Dissolution thermodynamic properties were calculated. Solubilities of guanidine hydrochloride (GuHCl) in organic solvents are of great importance for its development and optimization of industrial process. The study of the dissolution characteristics of GuHCl in DMF/2-meoxyethanol/methanol/NMP + n -propanol at different temperatures were experimentally investigated by using laser monitoring method. Results showed that GuHCl solubilities were observed to be increasing with the increment in experimental temperature and rising with higher mass fraction of DMF/2-meoxyethanol/methanol/NMP. Molecular dynamics (MD) simulation technique was utilized to reveal the microscopic behaviors of GuHCl and solvent mixtures and its effect on the dissolving capability of GuHCl in involved solvent systems. Also, five thermodynamic models were selected to regress the observed GuHCl equilibrium solubility. A comparison of the experimental values with corresponding estimated data indicated that the modified Apelblat equation provided the most excellent correlation in modelling GuHCl solubility. Finally, through the analyses of enthalpy change, entropy change and Gibbs free energy change, the dissolution thermodynamic features were evaluated. [ABSTRACT FROM AUTHOR]

• Solubility of CDON in twelve organic solvents was determined. • The dissolution order of CDON was analyzed by solvent effect. • Experimental solubility data were correlated with five thermodynamic models. • CDON dissolution was observed to be endothermic and entropy-driven. The solubility of cyclododecanone (CDON) was determined in twelve solvents containing acetonitrile, acetone, toluene, ethyl acetate, cyclohexane, 1,2-dichloroethane, methanol, ethanol, n -propanol, i -propanol, n -butanol and i -butanol. The temperature range for the remaining solvents used in the experiment was 278.15–313.15 K, except for cyclohexane (283.15–313.15 K). The CDON solubility in solvents measured increased with growing temperature. The CDON solubility varies considerably in different solvents. Among the single solvents selected, CDON was most soluble in 1,2-dichloroethane and least in acetonitrile. The solubility in 1,2-dichloroethane is about 2–3 times higher than in acetonitrile. The carbonyl oxygen of CDON readily combines with alcoholic solvents to form hydrogen bonds. Hansen solubility parameters (HSP) and the physiochemical properties of the solvents explain the solvent effect in diverse solvents. To understand CDON dissolution, the electrostatic potential energy surfaces of CDON and the solute–solvent interactions were analyzed at the molecular level on the basis of density functional theory (DFT). Analysis of solvation effects revealed that variations in the CDON dissolution are influenced by a combination of factors rather than a single one. In addition, the Van't Hoff equation, modified Apelblat equation, Yaws equation, λh equation, Wilson model and Jouyban model were utilized to correlate the experimentally obtained value. The computational data show that the ARD (0.88%) and RMSD (0.24%) of Wilson model are the smallest among the selected equations with the best correlation. The apparent thermodynamic properties of CDON dissolution were further accounted for Van't Hoff equation, and the CDON dissolution was observed to be endothermic and entropy-driven. [ABSTRACT FROM AUTHOR]

[Display omitted] • Inter/intra-molecular interactions of albendazole-solvent were examined. • Solubility of albendazole in three binary aqueous solutions were determined and correlated. • Preferential solvation were studied by using the IKBI method. • Solvent effect was investigated by EHSA model. • Dissolution properties as well as enthalpy–entropy compensation were studied. In this work, albendazole was dissolved in mixtures of acetone/methanol/isopropanol + water to examine its solubility, dissolution thermodynamics, solvation behavior, and intermolecular interactions. The shake-flask method was used to conduct solubility tests at a pressure of 101.0 kPa and temperatures from 278.15 to 323.15 K. In water and pure organic solvents, respectively, the lowest and greatest levels of albendazole solubility were found. XRD analysis-based experiments found no evidence of crystal solvation or transition. Jouyban-Acree, modified Wilson, QSPR and modified van't Hoff-Jouyban-Acree models correlated the solubility to solvent composition and temperature with the relative average deviations (RAD) of no more than 8.99 %. The equilibrium solubility at 298.15 K was examined using the approach of extended Hildebrand solubility parameter, which produced an average relative deviation of 3.63 %. The dipolarity-polarizability and solubility parameter of solutions have a considerable impact on the solubility fluctuation, according to the analysis of linear solvation energy relationship. The preferred solvation of albendazole by water and different organic solvents was quantitatively examined with the help of the inverse Kirkwood-Buff integrals. Albendazole was preferentially solvated by the organic solvents in moderate and rich organic solvent compositions in blends, where albendazole served as a Lewis acid. An enthalpy-driven mechanism and an endothermic process were identified by thermodynamic analysis of the entropy-enthalpy compensation and dissolution properties for albendazole dissolving in blends. The electrostatic characteristics of albendazole acidity/basicity were highlighted using analysis of Hirshfeld surface and molecular surface. The primary targets of nucleophilic and electrophilic assault are the –NH and -S-groups. An independent gradient model based on Hirshfeld partition analysis was used to visual the weak interactions between albendazole and different solvents. [ABSTRACT FROM AUTHOR]

[Display omitted] • The solubility of 2-amino-6-chloropyrazine in different solvents were determined. • The solubility data were calculated by different thermodynamic models. • Apparent thermodynamic properties were obtained by van't Hoff plots. • Preferential solvation of 2-amino-6-chloropyrazine was investigated by IKBI method. • The solvent effect of 2-amino-6-chloropyrazine was analyzed by KAT-LSER model. Equilibrium solubility of 2-amino-6-chloropyrazine in ten pure solvents (methanol, ethanol, n -propanol, isopropanol, N,N -Dimethylformamide (DMF), acetonitrile, acetone, propylene glycol (PG), ethylene glycol (EG) and water) and four binary blends of ethanol/ n -propanol/PG/DMF plus water was experimentally measured by isothermal saturation method at 278.15 K to 323.15 K under p = 101.2 kPa. The maximum mole fraction of 2-amino-6-chloropyrazine in mono-solvents was obtained in neat acetone (5.053 × 10-2) at 323.15 K. For four binary mixed systems, the amount of 2-amino-6-chloropyrazine dissolved in DMF + water was more than other three systems. For pure solvent systems, the temperature was the only factor that affected the dissolution of 2-amino-6-chloropyrazine, while temperature and solvent composition were both the factors that affected the dissolution of 2-amino-6-chloropyrazine. The solubility data of 2-amino-6-chloropyrazine in pure solvents was correlated with apelblat model, van't Hoff model and Buchowski–Książczak λh model. The Jouyban-Acree model, Apelblat-Jouyban-Acree model and van't Hoff-Jouyban-Acree model were applied to calculate the solubility data of 2-amino-6-chloropyrazine in mixtures. The van't Hoff plots of the solubility of 2-amino-6-chloropyrazine was adopted as a method to show the relationship between ln × and 1 /T- 1 /T hm , which was the basis for calculating thermodynamic properties. The preferential solvation performance in mixed systems was estimated by the values of δx 1,3 , in 0.19 < x n-propanol/PG/DMF < 1 and 0.23 < x ethanol < 1, the 2-amino-6-chloropyrazine was preferentially dissolved in organic solvents. In contrast, the 2-amino-6-chloropyrazine was dissolved preferentially in water in other intervals. What's more, the solvent effect of 2-amino-6-chloropyrazine in mixed systems was obtained, the hydrogen bond interaction was the only factor that affects dissolution in alcohols + water and the solvent–solvent molecular interaction was dominant in DMF + water. [ABSTRACT FROM AUTHOR]

The thermodynamic relationship between FI and FII of ethyl 4-aminobenzoate (benzocaine) has been investigated. Slurry conversion experiments show that the transition temperature below which FI is stable is located between 302 K–303 K (29 °C–30 °C). The polymorphs FI and FII have been characterised by infrared spectroscopy (IR), Raman spectroscopy, transmission powder X-ray diffraction (XRPD) and differential scanning calorimetry (DSC). The isobaric solid state heat capacities have been measured by DSC. The quantitative thermodynamic stability relationship has been determined in a comprehensive thermodynamic analysis of the calorimetric data. The solubility of both polymorphs has been determined in eight pure organic solvents over the temperature range 278 K–323 K by a gravimetric method. The mole fraction solubility of benzocaine decreases in the order: 1,4-dioxane, acetone, ethyl acetate, chloroform, acetonitrile, methanol, n -butanol and toluene. Comparison with the determined activity of solid benzocaine forms shows that negative deviation from Raoult's law ideality is found in dioxane, acetone and ethyl acetate solutions, and positive deviation in solutions of the other investigated solvents. [ABSTRACT FROM AUTHOR]

The solubility behavior and solution chemistry of CL-20/MTNP (2,4,6,8,10,12-hexanitro-hexaaza-isowurtzitane/1-methyl-3,4,5-trinitropyrazole) energetic cocrystals in organic solvents were first investigated to offer some important information on thermodynamics. The phase solubility diagram (PSD) and eutectic point (Keu1) of three solvents were also determined. Moreover, the solubility behavior of CL-20/MTNP energetic cocrystals was explained using the solubility product and solution complexation theories. The solution complexation results indicated that the CL-20/MTNP cocrystal has the strongest complexation effect in ethanol. The Keu1 values were all below 1 in three studied solvents, suggesting that the CL-20/MTNP cocrystal was less soluble than the other two pure components. Furthermore, studying the solubility behavior and solution chemistry of the CL-20/MTNP cocrystals has provided further insights into the screening, preparation and scaling-up of energetic cocrystals. [ABSTRACT FROM AUTHOR]

• Musk xylene in ten organic solvents at temperatures ranging from 278.15 K to 313.15 K was measured. • Analysis of musk xylene by XRD. • Wilson model, NRTL model, Vant't Hoff equation, modified Apelblat equation, and λh equation are used to correlate the solubility of musk xylene in different solvents. • The mixed Gibbs energy, enthalpy and entropy were calculated according to Wilson model. In this study, isothermal saturation method was used to measure and correlate the solubility of musk xylene in ten organic solvents at temperatures ranging from 278.15 K to 313.15 K , including methanol, ethanol, isopropanol, n-butanol, cyclohexane, n-hexane, n-heptane, N,N-dimethylacetamide, ethyl acetate, tetrahydrofuran. The experimental results show that the solubility of musk xylene in the selected solvent increases with increasing temperature. The experimental data were correlated by five thermodynamic models, and the results showed that each model can give a satisfactory correlation. In addition, the three kinds of mixed thermodynamic properties of Gibbs energy, enthalpy and entropy of musk xylene in selected solvents were determined by solubility data and Wilson model. It can be seen that the dissolution of musk xylene in a given solvent is spontaneous and entropy driven. Exploring the solubility of musk xylene in different organic solvents and the thermodynamics of dissolution can not only provide basic data for industrial crystallization separation, but also have great significance for its own crystallization and theoretical research. [ABSTRACT FROM AUTHOR]

The solubility of butamben has been measured gravimetrically in pure methanol, 1-propanol, 2-propanol, 1-butanol, and toluene over the temperature range 268-298 K. Polymorph transition and melting temperatures, associated enthalpy changes, and the heat capacity of the solid forms and the supercooled melt have been measured by differential scanning calorimetry. Based on extrapolated calorimetric data, the Gibbs energy, enthalpy and entropy of fusion, and the activity of solid butamben (the ideal solubility) have been calculated from below ambient temperature up to the melting point. Activity coefficients of butamben at equilibrium in the different solvents have been estimated from solubility data and the activity of the solid, revealing that all investigated systems exhibit positive deviation from Raoult's law. Solubility data are well correlated by a semiempirical regression model. On a mass basis, the solubility is clearly higher in methanol than in the other solvents, but mole fraction solubilities are very similar across all 5 solvents. The 2 known polymorphs are enantiotropically related, and the transition point is located at 283 K. Polymorph interconversions occur within 0.3 K of the transition point even in the solid state, and the 2 forms exhibit strong similarities in investigated properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • 18 β -Glycyrrhetinic acid solubility in four cosolvent solutions were determined and mathematically correlated. • Study on solubility behavior was made by the EHSA model. • Preferential solvation were investigated via inverse Kirkwood–Buff integrals method. • Dissolution thermodynamic properties as well as enthalpy–entropy compensation were studied. • Inter-molecular interactions of 18 β -glycyrrhetinic acid-solvent were investigated. This study investigated the solubility, solvation behavior, dissolution thermodynamics, and intermolecular interactions of 18 β -glycyrrhetinic acid (GA) in binary aqueous blends of 1,4-dioxane, N , N -dimethylformamide (DMF), ethanol and isopropanol. The solubility experiments were performed using the shake-flask technique at 101.0 kPa and temperatures ranging from 278.15 to 323.15 K. The lowest and highest GA solubility was observed in water and neat organic solvent, respectively. Experiments based on XRD analysis revealed no crystal transition or solvation. Modified van't Hoff–Jouyban–Acree and Jouyban–Acree models connected the solubility with relative average deviations (RAD) not exceeding 3.63 %. The extended Hildebrand solubility parameter method was utilized here to examine the equilibrium solubility at 298.15 K, yielding a RAD of 3.95 %. According to the linear solvation energy relationship examination, the dipolarity-polarizability and solubility parameter of solutions significantly influence the solubility variation. Using the inverse Kirkwood–Buff integrals, the preferential solvation of GA by organic solvents and water was investigated quantitatively. Positive preferential solvation parameter for organic solvents in rich and moderate organic solvent blends indicated that GA was preferentially solvated by the organic solvents. GA is a Lewis acid with respect to the cosolvent molecules. Thermodynamic investigation of dissolution characteristics and enthalpy–entropy compensation revealed an endothermic process and enthalpy-driven mechanism for dissolving GA in various blends. Finally, microscopic quantitative examination of molecular surface was used to highlight the electrostatic properties of acidity/basicity of GA. The –C = O, OH, and > COOH groups are the main targets of electrophilic and nucleophilic attack. The weak interactions between GA and solvent were visually examined using an independent gradient model based on Hirshfeld partition analysis. [ABSTRACT FROM AUTHOR]

• Solubility data of 1,4-cyclohexanedione in ten pure solvents were measured. • Experimental data were correlated by five thermodynamic models. • Dissolution mechanism of 1,4-cyclohexanedione in ten pure solvents was investigated. • Thermodynamic properties were discussed by Wilson model. As an important raw material in industrial production, the solubility studies of 1,4-cyclohexanedione (14CHD) in organic solvents may be of assistance in improving crystallization efficiency and yield in industry. Therefore, this work deeply explored the dissolution behavior of 14CHD by using the isothermal saturation method, model fitting and density functional theory (DFT) calculation. Firstly, we selected ten pure organic solvents that are environmentally friendly to measure the solubility of 14CHD at the temperature range of 278.15 ∼ 313.15 K under standard atmospheric pressure. According to the measurement results, the solubility of 14CHD increases with temperature, and there are some differences among the solubility of 14CHD in various solvents. For instance, it has a highest solubility in acetonitrile (x 1 = 0.5331) at 313.15 K while has the lowest solubility (x 1 = 6.757 × 10-4) in cyclohexane at 283.15 K. Whereafter, the measured solubility data was correlated by Van't Hoff equation, modified Apelblat equation, λh model, Yaws model and Wilson model. Among them, Yaws model represents the most accurate fitting outcomes. At the same time, the study results of mixing thermodynamic properties on the basis of Wilson model suggest that the dissolution processes of 14CHD in ten organic solvents are entropy-driven and spontaneous. Afterwards, in order to explain the large difference in solubility of 14CHD in ten organic solvents, we found that the dissolution of 14CHD depends mostly on the polarity (π) and cohesive energy density (CED), viewed from the physicochemical factors of solvents. Furthermore, we further studied intermolecular interactions between 14CHD and ten solvents through molecular electrostatic potential surface (MEPS) analysis and DFT methods. Results display that alcoholic and non-alcoholic solvents molecules have different sites of action with 14CHD and the absolute values orders of interaction energies of alcoholic and non-alcoholic solvents are all consistent with corresponding solubility laws. The solvent–solute interaction plays an important role in the solubilities of 14CHD. [ABSTRACT FROM AUTHOR]

Highlights • A cavity-based method to calculate relative solubilities of large solutes in pairs of solvents is presented. • The cavity-based method is benchmarked against direct molecular simulations employing coarse-grained fluid models. • Relative solubilities of pyrene in heptane and toluene are calculated at high pressures and temperatures. Abstract In this paper, we benchmark a cavity-based simulation method for calculating the relative solubility of large molecules in explicit solvents. The essence of the procedure is the accounting of the Gibbs energy change associated with an alchemical thermodynamic cycle where, in sequence, a cavity is created in a solvent, a solute is inserted in the cavity and the cavity is annihilated. The Gibbs energy change is equated to the excess chemical potential allowing the comparison of solubilities in different solvents. The results obtained using the cavity-based method are compared to direct large-scale molecular dynamics simulations performed using coarse-grained models for calculating the partition coefficient of pyrene between heptane and toluene. We demonstrate the applicability of this cavity-based technique under high pressure/temperature conditions. [ABSTRACT FROM AUTHOR]

The solubility of coumarin in three aqueous solvent mixtures (methanol + water, ethanol + water and acetone + water) was experimentally determined by a gravimetric method at atmospheric pressure. The experimental solubility data were fitted using the modified Apelblat equation, non-random two-liquid (NRTL) equation, the combined nearly ideal binary solvent/Redlich-Kister equation and the Jouyban−Acree equation, respectively. All the equations were proven to be able to correlate the experimental data, and the modified Apelblat equation could obtain better correlation results than the other three models. The solubility of coumarin increases with increase in temperature. At the same temperature, the solubility increases with increase in mole fraction of organic solvents except for the ethanol-water system which shows a unimodal curve. In addition, the apparent thermodynamic properties of the mixing process were calculated based on the NRTL model and the experimental solubility data. [ABSTRACT FROM AUTHOR]

Highlights • Errors are found in model coefficients for mathematical representations. • NRTL model coefficients fail to back-calculated observed solubility. • Coefficients of NRTL model were re-analyzed. Abstract Errors were discovered regarding the published equation coefficients of Yao and co-workers (2017) for mathematically describing the solubility of 3,5-dimethylpyrazole in nine organic solvents using the NRTL model. Larger differences were found between our back-calculated data and those reported in the authors' published paper. The equation parameters were re-regressed based on the reported solubility data. [ABSTRACT FROM AUTHOR]

Highlights • Errors are found in model coefficients for mathematical representations. • Apelblat equation coefficients fail to back-calculated observed solubility. • Jouyban-Acree model coefficients give very poor back-calculations. • Coefficients of modified Apelblat and Jouyban-Acree models were re-analyzed. Abstract Errors are discovered regarding the published equation curve-fit coefficients of Zhou et al. [1] for mathematically describing the solubility of l -Theanine in pure water and three kinds of water + organic solvent mixtures using the modified Apelblat equation and Jouyban-Acree model. The calculated values using the published equation coefficients for the two models do not correctly describe the determined solubility data as stated in the published paper. In addition, the equation parameters were re-analysed based on the reported solubility data. [ABSTRACT FROM AUTHOR]

Although β-lapachone is a promising drug with pharmacological activity, issues concerning its low aqueous solubility are known. The objective of this study was to measure the solubility of β-lapachone in water and ten organic solvents at temperatures ranging from 298.15 K to 318.15 K under atmospheric pressure. The modified Apelblat model, the Buchowski-Ksiazaczak λh model, and the ideal model were used to correlate experimentally obtained solubility values. Moreover, thermodynamic analysis of β-lapachone dissolution was performed based on experimental solubility data using the van't Hoff equation. The highest mole fraction solubility of β-lapachone at 298.15 K was found in acetone (2.05 × 10 −2 ), followed by acetonitrile (1.80 × 10 −2 ), ethyl acetate (8.53 × 10 −3 ), 1-butanol (7.43 × 10 −3 ), 1-propanol (6.69 × 10 −3 ), 2-butanol (5.65 × 10 −3 ), methanol (5.40 × 10 −3 ), ethanol (4.99 × 10 −3 ), 2-propanol (3.76 × 10 −3 ), propylene glycol (3.06 × 10 −3 ), and water (2.85 × 10 −6 ). Correlation results showed that the modified Apelblat model was more accurate than the Buchowski-Ksiazaczak λh model and the ideal model. Thermodynamic analysis indicated that β-lapachone dissolution was endothermic and entropy-driven process in all solvents studied. Data on solubility and thermodynamic properties in various solvents obtained in this study could be helpful in formulation development, purification, and crystallization of β-lapachone. [ABSTRACT FROM AUTHOR]

The solubility of deferiprone (DFP) in five organic solvents including ethyl acetate, chloroform, acetonitrile, 1,4-dioxane and dichloromethane was investigated by the flask-shake method under atmospheric pressure at temperatures ranging from 293.15 to 313.15 K. In general, the solubility (mol L-1) obeyed the following order from high to low in different mono-solvents: dichloromethane > chloroform > acetonitrile > 1,4-dioxane > ethyl acetate. The solubility of DFP in the mono-solvents increased with a rise of temperature. The solubility data were successfully correlated with the van’t Hoff equation. The generated data in this work and the previously published data were used to calculate the thermodynamic parameters of the system using the modified van’t Hoff equation, and the derived thermodynamic properties were correlated using Abraham solvation parameters. [ABSTRACT FROM AUTHOR]

The solubility of 3-methyl-2-nitrobenzoic acid in nine organic solvents: methanol, ethanol, n-propanol, isopropanol, ethyl acetate, acetone, acetonitrile, 1,4-dioxane and N-methyl-2-pyrrolidone (NMP) was determined using the isothermal saturation method over a temperature range from 283.15 to 318.15 K under atmospheric pressure (101.2 kPa). Within the temperature range studied, the mole fraction solubility of 3-methyl-2-nitrobenzoic acid in the solvents increased with a rise of temperature. The solubilities obey the following order from high to low in different solvents: 1,4-dioxane > acetone > NMP > methanol > ethanol > (ethyl acetate, isopropanol) > n-propanol > acetonitrile. The solubility data of 3-methyl-2-nitrobenzoic acid in the studied solvents was correlated by using the λh equation, Wilson model and NRTL model. The maximum values of root-mean-square deviation and relative average deviation are 1.60 × 10−4 and 0.57%, respectively. In general, the selected models are all acceptable for describing the solubility of 3-methyl-2-nitrobenzoic acid in these solvents. In addition, the solvent effect was studied by using the Kamlet-Taft linear solvation energy relationship. The type and extent and direction of solute-solvent interactions were identified. Furthermore, the dissolution Gibbs energy, dissolution enthalpy, dissolution entropy, activity coefficient at infinitesimal concentration (γ1∞) and molar excess enthalpy (H1E,∞) were evaluated. The solubility data and thermodynamic studies will be very helpful for optimizing the purification process of 3-methyl-2-nitrobenzoic acid from its isomer mixtures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solubility data of paliperidone palmitate racemic mixture in 21 kinds of mono-solvents were determined. • Different thermodynamic models were used to correlate solubility data. • Solubility increases with the increasing of temperature. • Dissolution properties of paliperidone palmitate were calculated based on the Wilson model. Solid-liquid equilibrium solubility paliperidone palmitate (PP) in 21 kinds of mono-solvents, including ethanol, n -propanol, i -propanol, n -butanol, i -butanol, s -butanol, n -pentanol, i -pentanol, 2-butanone, methyl isobutyl ketone, cyclohexanone, ethyl formate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, amyl acetate, N , N -dimethylformamide (DMF), tetrahydrofuran (THF), toluene, and 1,4‑dioxane were determined by a gravimetric method at a various temperature. The solubility of PP increases with the increase of temperature. In alcoholic solvents, the solubility order is: n -pentanol > i -pentanol > i -butanol > s -butanol > n -butanol > n -propanol > i -propanol > ethanol. In easter solvents, the solubility of PP ranking as: ethyl formate > amyl acetate > butyl acetate > propyl acetate > ethyl acetate > isopropyl acetate. For ketone solvent, the solubility order is: cyclohexanone > 2-butanone > methyl isobutyl ketone. In other solvents, the solubility order is: THF > toluene > 1,4‑dioxane > DMF. The maximum solubility of PP is 0.1922 mol·mol−1 (toluene, 353.15 K), and the minimum solubility is 0.0003788 mol·mol−1 (ethanol, 318.15 K). Four thermodynamic models, i.e., the modified Apelblat model, the Yaws model, the NRTL model and the Wilson model were selected to correlate the solubility data in this paper. NRTL model fits best among all the models with RAD no larger 4.84 × 10−2 (n -propanol) and RMSD value less than 12.55 × 10−4 (1,4-dioxane). Furthermore, dissolution thermodynamic properties of PP were evaluated based on the Wilson model. The dissolution process of PP is demonstrated to be spontaneous in the chosen organic solvents. [ABSTRACT FROM AUTHOR]

The solubility of florfenicol form A in eight pure organic solvents (propionic acid, ethanol, 1-propanol, 1-butanol, 2-propanol, 2-methyl-1-propanol, 3-methyl-1-butanol, and 2-ethyl-1-hexanol) and three binary solvents (dimethyl sulfoxide + ethanol, dimethyl sulfoxide + 1-propanol, and dimethyl sulfoxide + 1-butanol) was measured by a laser dynamic method at temperature from 283.15 to 323.15 K. The experimental results show that the mole fraction solubility of florfenicol in the pure solvents decreased according to the following order: ethanol > 1-propanol > 2-propanol > 1-butanol > 3-methyl-1-butanol > 2-methyl-1-propanol ≈ propionic acid > 2-ethyl-1-hexanol. The experimental results show that the mole fraction solubility of florfenicol form A in the binary solvents increased with the increase of temperature and dimethyl sulfoxide mass fraction. The experimental solubility data were well correlated with the four thermodynamic models: modified Apelblat equation, Λh equation, NRTL model equation, and Wilson model equation. The modified Apelblat model equation was regarded as the best one to fit the experimental values in the pure solvents. [ABSTRACT FROM AUTHOR]

The solubility of 2,3,5,4′-tetrahydroxystilbene-2- O - β -D-glucoside (THSG) was measured in nine organic solvents (methanol, ethanol, n -propanol, i -propanol, ethyl acetate, acetone, acetonitrile, N , N -dimethylformamide (DMF), and tetrahydrofuran (THF)) in the temperature range 278.15 to 318.15 K at atmosphere pressure by the gravimetrical method. In the temperature range considered, the solubility of THSG in all of the solvents increases with increasing temperature. At a given temperature, the solubility of THSG in the different solvents is in the order DMF > THF > acetone > methanol > ethanol > n -propanol > i -propanol > ethyl acetate > acetonitrile. The solubility data of THSG are well correlated with the modified Apelblat equation, Buchowski–Książczak λ h equation, and Van't Hoff equation. The correlation shows good agreement with the experimental results, and the largest values of the relative average deviation and root-mean-square deviation are 2.37 × 10 −2 and 4.53 × 10 −4 , respectively. The apparent dissolution enthalpy and excess enthalpy of the solutions were also investigated. [ABSTRACT FROM AUTHOR]

The addition of organic solvents, such as ethanol, to molecules in solution is an effective process for crystallization and is used in industrial settings (i.e. pharmaceutical production, downstream processing, etc.). In this study, we use solubility data of all proteinogenic α-amino acids in binary ethanol/water systems to model their excess solubility. We use the empirical and regressive models of Gude and NRTL and the predictive Jouyban-Acree model. Based on the results, we hypothesize that amino acids that are spherical and lack a reactive side chain show little or no excess solubility. Being rod-like and/or having a reactive side chain leads to a positive excess solubility in a mixed solvent of ethanol and water. The empirical and regressed models, NRTL and Gude, fit the data well and the predictive Jouyban-Acree model, not originally intended to be used for small molecules, is less accurate but offers insights into the thermodynamic properties of the amino acids. [ABSTRACT FROM AUTHOR]

In order to provide a database for supporting stability in the separation processes, the physical properties of the mixing solutions between extractant and organic solvents, with/without water, were investigated at temperature 303.2 K and pressure 0.1 MPa. The extractant of tributyl phosphate (TBP) as well as the following organic solvents i.e. cyclohexane, n -heptane, kerosene and toluene were selected for use in this work. Further, the physical properties of the mixing solutions such as viscosity, surface tension, interfacial tension and solubility with water were observed when the percent weights of the extractant increased. The principle of intermolecular attraction between the molecules in the mixing solutions was considered in order to explain the tendencies of results. Tie-line data were determined for ascertaining the solubility of extractant in the organic and aqueous phases. A thermodynamic NRTL model was also evaluated and its data compared with the experimental results. Consequently, good correlations were displayed by the root-mean square deviation ( rmsd ) at values about 2%. Finally, for understanding the solvation of solute and solvent, the molecular interaction behaviors of the molecules in the mixing solutions were examined by spectroscopic analyses. [ABSTRACT FROM AUTHOR]

The target of this work is to measure and correlate the solubility of Raspberry Ketone, and obtain the thermodynamic parameters simultaneously. In this study, the solubility of Raspberry Ketone in nine mono-solvents, including ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, acetic acid, methyl acetate, ethyl acetate, acetone, and binary mixtures of ethanol + acetone (the mass fraction of ethanol varied from 0.1 to 0.9, in intervals of 0.1) was measured at (293.15 to 333.15) K in atmospheric pressure by shake-flask method. The solubility of Raspberry Ketone both in mono- solvents and mixtures increased as the temperature increased. The deliquescent rules can be acquired by using modified Apelblat equation, van't Hoff equation, λh equation, Wilson model, Non-Random Two Liquid (NRTL) model, Universal Quasi–Chemical (UNIQUAC) Model and modified Jouyban-Acree model. The experimental data show highly conformance with the calculated data which obtain from all the selected models. Consequently, the solubility results of this study would be useful in purification, crystallization, recrystallization and a new synthetic route design of Raspberry Ketone. [ABSTRACT FROM AUTHOR]

The solubilities of 3-nitrobenzonitrile in 12 organic solvents including methanol, ethanol, n-propanol, isopropanol, acetone, n-butanol, 2-methyl-1-propanol, acetonitrile, acetic acid, ethyl acetate, cyclohexane, and toluene were measured by the static method within the temperature range from (278.15 to 318.15) K under atmospheric pressure of 101.1 kPa. The mole fraction solubility of 3-nitrobenzonitrile in the selected solvents increased with a rise in temperature. In general, they ranked as acetone > (acetonitrile, ethyl acetate) > toluene > acetic acid > methanol > ethanol > n-propanol > n-butanol > isopropanol >2-methyl-1-propanol > cyclohexane. The achieved solubilities of 3-nitrobenzonitrile were correlated via the λh equation, modified Apelblat equation, NRTL model, and Wilson model. The maximum relative average deviation and root-mean-square deviation were 1.87% and 2.399 × 10-3, respectively. Finally, the mixing properties, e.g., change in Gibbs energy, enthalpy, entropy, activity coefficient at infinitesimal concentration, and reduced excess enthalpy, were also derived on the basis of the Wilson model. The mixing process of 3-nitrobenzonitrile in these solvents was endothermic and spontaneous. [ABSTRACT FROM AUTHOR]

We focused on the solubility of olaparib under atmospheric pressure in isopropyl alcohol, MTBE, acetonitrile, and tetrahydrofuran as well as in the (tetrahydrofuran + MTBE, acetonitrile + isopropyl alcohol) mixtures from 280.35-319.35 K. It is found that the solubility of olaparib and temperature were positively correlated in the range of our study. We chose the modified Apelblat equation, the Buchowski-Ksiazaczak λh equation, CNIBS/R-K equation, and the Jouyban-Acree equation to verify the thermodynamic properties of olaparib. Computational results showed that all selected equations agreed well with the experimental data, and the modified Apelblat equation gives the best correlation. We also selected two binary solvent dissolution systems, and the test found that (tetrahydrofuran + MTBE) mixtures may be a good recrystallization system. This study provides valuable data for olaparib's production process purification. [ABSTRACT FROM AUTHOR]

This paper concerns the solubility of maleic acid, using inorganic salts and organic solvents. Several types of organic solvents were investigated such as methyl isobutyl ketone (MIBK), n-butanol, toluene, ethyl acetate and ethyl methyl ketone. Results showed that the solubility of maleic acid increased as follows: n-butanol > ethyl methyl ketone (EMK) > methyl isobutyl ketone (MIBK) > ethyl acetate (EA) >toluene. The effect of inorganic salts on the solubility of maleic acid was also investigated and was found accordingly: LiCl > NaCl > KCl > CaCl 2 > MgCl 2 > BaCl 2 > ZnCl 2 . In order to investigate thermodynamics parameters, temperatures ranging from 303.15 to 333.15 K were explored. As temperature increased, the efficiency of solubility of maleic acid increased. Correlations, based on the Gibbs–Helmholtz equation and the Van't Hoff equation, were used to calculate Gibbs energy, enthalpy and entropy and to explain the thermodynamic properties for the solution process. The positive value of enthalpy and the negative value of Gibbs free energy were endothermic and nonspontaneous, respectively for the dissolution process of maleic acid. In order to predict the experimental data, thermodynamic models, such as the Buchowski–Ksiazaczak λh model, the modified Apelblat model and NRTL, were investigated. NRTL proved to be the most suitable for predicting the solubility behavior of maleic acid with temperature exhibiting low values of R A D and R M S D . [ABSTRACT FROM AUTHOR]

The solid-liquid equilibrium of 2-mercaptobenzothiazole in eleven solvents of methanol, n -propanol, i -propanol, n -butanol, i -butanol, acetonitrile, ethyl acetate, toluene, 2-butanone, chloroform and 1,4-dioxane was investigated by the isothermal dissolution equilibrium method under atmosphere pressure of 101.2 kPa, and the solubilities were determined by a high-performance liquid chromatography at T = (273.15, 275.65, 278.15, 280.65, 283.15, 285.65, 288.15, 290.65, 293.15, 295.65, 298.15, 300.65, 303.15, 305.65, 308.15, 310.65, 313.15, 315.65 and 318.15) K. For the eleven solvents, the mole fraction solubility of 2-mercaptobenzothiazole increased with increasing temperature. Thee obeyed the following order from high to low in different solvents: 2-butanone > 1,4-dioxane > ethyl acetate > n -butanol > n -propanol > i -butanol > i -Propanol > methanol > chloroform > acetonitrile > toluene. The solubility values obtained for 2-mercaptobenzothiazole in the selected solvents were correlated with four models, which corresponded to modified Apelblat equation, λh equation, Wilson model and NRTL model. The largest values of relative average deviation and the root-mean-square deviation acquired with the four models were 0.59 % and 4.86 × 10 −4 , respectively. Generally, the four thermodynamic models were all acceptable for describing the solubility behaviour of 2-mercaptobenzothiazole in the solvents. In addition, based on the Wilson model, the mixing thermodynamic properties (mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration and reduced excess enthalpy) of solutions were derived. The results indicated that the dissolution of 2-mercaptobenzothiazole in all studied cases was spontaneous and favourable. The solubility values and thermodynamic relations of 2-mercaptobenzothiazole in selected solvents would be invoked as fundamental data and models regarding the purification process of 2-mercaptobenzothiazole. [ABSTRACT FROM AUTHOR]

In this study, the solid-liquid equilibrium of 4-hydroxybenzaldehyde in twelve solvents including methanol, ethanol, n -propanol, 1-butanol, isopropanol, ethyl acetate, 2-butanone, acetonitrile, toluene, N , N -dimethylformamide, 1,4-dioxane and acetone were constructed by the isothermal dissolution equilibrium method at a temperature range from (278.15 to 318.15) K under atmospheric pressure (101.2 kPa), and the solubility values of 4-hydroxybenzaldehyde in these solvents were determined by a high-performance liquid chromatography. The mole fraction solubility increased with increasing temperature and obeyed the following order from high to low in different solvents except for 1,4-dioxane: N , N -dimethylformamide > 2-butanone > acetone > ethyl acetate > (1-butanol, isopropanol) > n -propanol > ethanol > methanol > acetonitrile > toluene. The modified Apelblat equation, λh equation, Wilson model and NRTL model were used to correlate the solubility of 4-hydroxybenzaldehyde in different solvents. Results showed that the largest values of relative average deviation and root-mean-square deviation obtained with the four models were 2.66% and 78.9 × 10 − 3 , respectively. Moreover, the mixing properties including the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration and reduced excess enthalpy were calculated. The solution process of 4-hydroxybenzaldehyde was spontaneous and favorable in the selected solvents. The solubility data and thermodynamic studies would be invoked as fundamental data and models regarding purification process of 4-hydroxybenzaldehyde and optimization conditions for its bromination process. [ABSTRACT FROM AUTHOR]

The solid-liquid equilibrium data of erythromycin ethylsuccinate in six pure organic solvents including tetrahydrofuran, acetone, acetonitrile, hexane, ethanol and 2-propanol were determined by using the gravimetric method over the temperature range from 288.15 K to 323.15 K. The experimental solubility data was correlated by modified Apelblat equation, van't Hoff, Wilson, and NRTL model, among which the modified Apelblat model was found to have the best agreement with the experimental results. The mixing Gibbs free energy, mixing enthalpy, and mixing entropy were calculated by Non-random two liquid (NRTL) model. The solubility behavior of EES at given temperature were illustrated by Hansen SPs values. [ABSTRACT FROM AUTHOR]

Solubility of 3,5-dimethylpyrazole in nine organic solvents including ethanol, isopropanol, n -propanol, 1-butanol, methanol, ethyl acetate, toluene, acetone, acetonitrile was determined experimentally by using the isothermal saturation method over a temperature range from (283.15 to 313.15) K under 101.3 kPa. For the temperature range studied, the solubility of 3,5-dimethylpyrazole in the solvents increased with a rise of temperature. In general, they obeyed the following order from high to low in different solvents: 1-butanol > n -propanol > (ethanol, isopropanol, methanol, ethyl acetate, acetone) > toluene > acetonitrile. The acquired solubility data of 3,5-dimethylpyrazole in the studied solvents were correlated by using the modified Apelblat equation, λh equation, Wilson model and NRTL model. The maximum values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 3.293 × 10 −3 and 2.62%, respectively. The RAD values acquired with the modified Apelblat equation were smaller than those with the other three models for a certain solvent except for the system of n -propanol. Generally, the four thermodynamic models were all acceptable for the systems of 3,5-dimethylpyrazole in these solvents. Furthermore, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were obtained. The solution process of 3,5-dimethylpyrazolewas spontaneous in the studied solvents. The obtained solubility and thermodynamic studies would be very helpful for optimizing the purification process of 3,5-dimethylpyrazole. [ABSTRACT FROM AUTHOR]

The knowledge of solubility and solution thermodynamics for 4-methyl-2-nitroaniline in different solvents is essential for its preparation, purification and further theoretical studies. In this work, the solid-liquid equilibrium for 4-methyl-2-nitroaniline in fourteen organic solvents (methanol, ethanol, n -propanol, isopropanol, n -butanol, toluene, ethyl acetate, acetonitrile, 2-butanone, 1,4-dioxane, N , N -dimethylformamide, carbon tetrachloride, 1,2-dichloroethane and chlorobenzene) was built with the isothermal saturation method at temperatures T = (278.15–318.15) K under pressure of 101.2 kPa, and the solubility values of 4-methyl-2-nitroaniline in these solvents were determined by a high-performance liquid chromatography (HPLC). Generally, the mole fraction solubilities obeyed the following order from high to low in different solvents: 2-butanone > N , N -dimethylformamide > ethyl acetate > 1,4-dioxane > (acetonitrile, 1,2-dichloroethane) > chlorobenzene > (toluene, n -butanol) > n -propanol > isopropanol > ethanol > methanol > carbon tetrachloride. The obtained solubility data of 4-methyl-2-nitroaniline in the selected solvents were correlated with the modified Apelblat equation, λh equation, Wilson model and NRTL model. Results showed that the largest values of relative average deviation and root-mean-square deviation acquired with the four models were no greater than 1.03% and 6.89 × 10 −4 , respectively. The modified Apelblat equation provided better correlation results than the other three models. Moreover, the mixing properties, including mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration and reduced excess enthalpy were computed. The mixing process of 4-methyl-2-nitroaniline in the studied solvents was spontaneous and endothermic. The obtained solubility and thermodynamic studies would be very helpful for optimizing the preparation and purification process of 4-methyl-2-nitroaniline. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solubility of 2-aminoterephthalic acid is measured in 8 monohydroxy alcoholic solvents. • Van't Hoff and Buchowski model satisfactorily describe the data. • The KAT-LSER model was used to explore the solvation effect. • Dissolution entropy and enthalpy show a volcano-type relation with solvent boiling point. This research experimentally measured the solubility of 2-aminoterephthalic acid in eight pure alcoholic solvents – methanol, ethanol, 1-propanol, 1-butanol, 2-propanol, 2-butanol, 2-methyl-2-propanol, and 3-methyl-1-butanol – from 303.15 to 338.15 K at normal pressure p = 0.1 MPa by the excess solid method. The measured solubility of 2-aminoterephthalic acid in these pure organic solvents was found to increase with the rise of temperature in the following order: 3-methyl-1-butanol (lowest solubility) < 1-butanol < 2-butanol < 1-propanol < 2-methyl-2-propanol ≈ 2-propanol < ethanol < methanol (highest solubility). The experimental solubility was correlated by the Van't Hoff equation and the λh (Buchowski) equation. The apparent thermodynamic properties (Δ0G sol , Δ0H sol and Δ0S sol) were calculated by the Van't Hoff equation, from which it was concluded that the dissolution process is entropy-motivated and endothermal. In addition, the solvent effects on 2-aminoterephthalic acid solubility were studied by the KAT-LSER model, where the results showed that the polarizability accounts for 47.9 ± 4.2 % of the total solvent effect. A volcano-type relation between the dissolution entropy and enthalpy versus the solvent boiling point is reported, showing maximal values of 55.3 J mol−1 K−1 and 29.2 kJ mol−1, respectively, for intermediate molecular interactions of solute and solvent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solubility of thioxanthone in twelve pure solvents was measured. • Solubility data were correlated by Apelblat, λh , Wilson and NRTL model. • Thermodynamic properties of mixing process were calculated and discussed. The 9 H -thioxanthen-9-one (TX) solubilities in twelve pure organic solvents were measured from 292.15 K to 335.95 K with the synthetic method at normal pressure. It was found that the TX solubilities increased with temperature. The measured solubilities of TX are well correlated by modified Apelblat equation, λh equation, Wilson equation and non-random two liquid (NRTL) equation, and the Wilson equation provides the best fitting results. The mixing thermodynamic functions including the mixing Gibbs free energy, mixing enthalpy and mixing entropy are calculated using the activity coefficients obtained from the Wilson equation model. The results suggest that the solubility behavior of TX may be determined mainly by the enthalpy, whereas the intermolecular interactions, especially the hydrogen bonds, between the TX and solvent molecules play important roles for the solubilities of TX. [ABSTRACT FROM AUTHOR]

Solubility of 2-amino-5-methylthiazole in methanol, ethanol, n -propanol, isopropanol, acetone, 2-butanone, acetonitrile, ethyl acetate, toluene, 1,4-dioxane and cyclohexane were determined by using the isothermal saturation method over a temperature range from (278.15 to 313.15) K under atmosphere pressure (101.2 kPa). The solubility of 2-amino-5-methylthiazole in the studied solvents increased with the increase in temperature, and the mole solubility obeyed the following order from high to low in different solvents: methanol > ethyl acetate > acetone > ethanol > 1,4-dioxane > (2-butanone, n -propanol) > isopropanol > acetonitrile > toluene > cyclohexane. The attained solubility data of 2-amino-5-methylthiazole were correlated by using the modified Apelblat equation, λh equation, Wilson model and NRTL model. The maximum values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 10.66 × 10 − 4 and 1.74%, respectively. Furthermore, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration and reduced excess enthalpy were evaluated. [ABSTRACT FROM AUTHOR]

Solubility of 2-isopropylimidazole in nine organic solvents including methanol, ethanol, n -propanol, isopropanol, acetone, acetonitrile, ethyl acetate, toluene, 2-butanone and liquid mixture of (methanol + ethyl acetate) were determined experimentally by using the isothermal saturation method over the temperature range from (278.15 to 313.15) K under atmosphere pressure (101.2 kPa). The solubility of 2-isopropylimidazole in the pure solvents increased with a rise of temperature. In general, the mole fraction solubility obeyed the following order from high to low in different pure solvents: methanol > ethanol > 2-butanone > n -propanol > acetone > isopropanol > ethyl acetate > acetonitrile > toluene. For the (methanol + ethyl acetate) mixture with given initial composition, the mole fraction solubility of 2-isopropylimidazole increase with increasing temperature and mass fraction of methanol. The obtained solubility of 2-isopropylimidazole in the pure solvents was correlated with the modified Apelblat equation and λh equation; and in the binary solvent mixture, the Jouyban–Acree model, van’t Hoff–Jouyban–Acree model and modified Apelblat–Jouyban–Acree model. The maximum values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 19.29 × 10 −3 and 1.07%, respectively. In addition, the standard dissolution enthalpy was calculated. [ABSTRACT FROM AUTHOR]

The solubility of tebuconazole in nine organic solvents including methanol, ethanol, isopropanol, n -propanol, ethyl acetate, toluene, acetone, 2-butanone and acetonitrile was determined experimentally by using the isothermal saturation method over a temperature range from (278.15 to 313.15) K under 101.2 kPa. For the temperature range investigated, the mole fraction solubility of tebuconazole in the solvents increased with a rise of temperature. On the whole, they obeyed the following order from high to low in different solvents: 2-butanone > acetone > (ethyl acetate, toluene) > methanol > ethanol > isopropanol > n -propanol > acetonitrile. The acquired solubility data of tebuconazole in the studied solvents were correlated by using the modified Apelblat equation, λh equation, Wilson and NRTL models. The maximum values of root-mean-square deviation ( RMSD ) was 12.35 × 10 −4 , and the relative average deviation ( RAD ), 1.56%. Generally, the four thermodynamic models could all be employed to describe the solubility behaviour of tebuconazole in these solvents, and the modified Apelblat equation correlated the experimental data best according to the result of Akaike Information Criterion ( AIC ) analysis. Furthermore, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E , ∞ ) were computed. The solubility obtained and thermodynamic studies should be very helpful for optimizing the purification process of tebuconazole. [ABSTRACT FROM AUTHOR]

By the isothermal saturation method, the solid-liquid equilibrium of 4-nitro-1,2-phenylenediamine in eleven organic solvents (methanol, ethanol, n -propanol, isopropanol, acetone, 2-butanone, acetonitrile, ethyl acetate, n -butanol, toluene and 1,4-dioxane) was obtained experimentally within temperature range from (283.15 to 318.15) K under atmospheric pressure, and the solubility values of 4-nitro-1,2-phenylenediamine in these solvents were determined by a high-performance liquid chromatography (HPLC). Within this temperature range, the mole fraction solubility of 4-nitro-1,2-phenylenediamine in selected organic solvents increased with increasing temperature. The descending order of the solubility values was as follows: acetone > 2-butanone > 1,4-dioxane > ethyl acetate > acetonitrile > methanol > ethanol > isopropanol > n -propanol > n -butanol > toluene. The solubility values for 4-nitro-1,2-phenylenediamine in the selected solvents were correlated and calculated by using the modified Apelblat equation, λh equation, Wilson model and NRTL model. Results showed that the largest values of RAD and RMSD obtained by the four models were 1.53% and 0.83 × 10 −4 , respectively. The modified Apelblat equation can correlate the experimental results best according to the result of AIC analysis. Moreover, the mixing properties including the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E , ∞ ) were calculated. The solution process of 4-nitro-1,2-phenylenediamine is spontaneous and favourable in the selected solvents. Knowledge of solubility and associated thermodynamic studies are important in optimizing the purification process of 4-nitro-1,2-phenylenediamine. [ABSTRACT FROM AUTHOR]

The knowledge of solubility and solution thermodynamics for 2-methyl-4-nitroaniline in different solvents is essential for its purification and further theoretical studies. In this work, the solid-liquid equilibrium for 2-methyl-4-nitroaniline in eleven pure organic solvents (methanol, ethanol, n -propanol, isopropanol, n -butanol, toluene, ethyl acetate, acetonitrile, 2-butanone, acetone and cyclohexane) was established with the isothermal saturation method at temperatures T = (278.15–313.15) K under pressure of 101.2 kPa, and the solubility of 2-methyl-4-nitroaniline in these solvents were determined by a high-performance liquid chromatography (HPLC). In general, the mole fraction solubility obeyed the following order from high to low in different solvents: 2-butanone > acetone > ethyl acetate > acetonitrile > methanol > ethanol > n -propanol > n -butanol > isopropanol > toluene > cyclohexane. The modified Apelblat equation, λh equation, Wilson model and NRTL model were employed to correlate the measured solubility values of 2-methyl-4-nitroaniline in the selected solvents. Results show that the largest values of RAD and RMSD obtained with the four models are no greater than 0.71% and 3.27 × 10 −4 , respectively. The modified Apelblat equation provided better results than the other three models. Furthermore, the mixing properties, including Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were computed. The dissolution process of 2-methyl-4-nitroaniline is spontaneous and favourable in the selected solvents. The solubility and associated models would be very useful for optimizing the separation process of the isomeric mixtures of 2-methyl-4-nitroaniline and 2-methyl-6-nitroaniline. [ABSTRACT FROM AUTHOR]

Solubilities of 5-chloro-1-methyl-4-nitroimidazole in eleven organic solvents of methanol, ethanol, isopropanol, n -propanol, N -methyl-2-pyrrolidone, ethyl acetate, toluene, acetone, 2-butanone, trichloromethane and 1,4-dioxane were measured by using an isothermal saturation method at temperatures between 283.15 K and 318.15 K under 101.3 kPa. For the temperature range investigated, the solubilities of 5-chloro-1-methyl-4-nitroimidazole in these solvents increased with the increase in temperature. Overall, the mole fraction solubility obeyed the following order from high to low in different solvents: N -methyl-2-pyrrolidone > acetone > 2-butanone > trichloromethane > ethyl acetate > 1,4-dioxane > methanol > ethanol > toluene > n -propanol > isopropanol. The solubility values obtained for 5-chloro-1-methyl-4-nitroimidazole in the selected solvents were correlated via the λh equation, modified Apelblat equation, NRTL model and Wilson model. The largest value of root-mean-square deviation ( RMSD ) was 9.20 × 10 −4 , and the relative average deviation ( RAD ), 2.86%. The RAD values obtained with the modified Apelblat equation were smaller than those with the other three models except for the solvents of acetone and ethanol. Generally, the four thermodynamic models were all acceptable for describing the solubility of 5-chloro-1-methyl-4-nitroimidazole in the solvents. Moreover, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were achieved. The solution process of 5-chloro-1-methyl-4-nitroimidazole was spontaneous and favourable in the solvents selected. The solubility values and thermodynamic studies would provide a fundamental basis for optimizing the purification process of 5-chloro-1-methyl-4-nitroimidazole. [ABSTRACT FROM AUTHOR]

The solubility data of l -Theanine in pure water and three kinds of water + organic solvent mxitures were measured in temperature ranges from (278.15 to 13.15) K by using an equilibrium method. The results show that the solubility of l -Theanine increases with the increasing of temperature in all selected solvents. The modified Apelblat equation and the λ-h model were applied to correlate the solubility data in pure water, while the modified Apelblat equation, the λ-h model, the NRTL model and the Jouyban–Acree model were applied to correlate the solubility data in binary solvent mixtures. Furthermore, the mixing thermodynamic properties of l -Theanine in different solvents were also calculated based on the NRTL model and experimental solubility data. [ABSTRACT FROM AUTHOR]

The solubility of ciclesonide in seven organic solvents (ethanol, 2-propanol, 1-propanol, 1-butanol, acetonitrile, toluene and ethyl acetate) in the temperature range from 278.15 K to 313.15 K was measured by gravimetrical method under atmospheric pressure. The results indicate that the solubility of ciclesonide increases with elevating temperature in all investigated solvents. The solubility order in different solvents was interpreted through comparing interaction force between solute and solvent molecules by virtue of density function theory (DFT). Thermodynamic equations including the modified Apelblat equation, λh equation, Wilson equation and NRTL equation are all suitable to correlate the solubility results. Based on the Wilson equation, the thermodynamic parameters from the mixing process are calculated, and the results indicate the mixing process of ciclesonide in the selected pure solvents is spontaneous and entropy-driven. [ABSTRACT FROM AUTHOR]

In this study, the solubility of pranlukast hemihydrate in methanol, ethanol, 1-propanol, 2-propanol, and 1-butanol was determined at temperatures ranging from 298.15 to 323.15 K by a solid-liquid equilibrium method. The measured solubility data of pranlukast hemihydrate were correlated with the modified Apelblat and Van't Hoff models. The maximum mole fraction solubility of pranlukast hemihydrate in 1-butanol was observed to be 26.39 × 10 − 5 at 323.15 K, followed by that in 1-propanol (9.63 × 10 − 5 at 323.15 K), ethanol (6.18 × 10 − 5 at 323.15 K), 2-propanol (5.71 × 10 − 5 at 323.15 K), and methanol (3.96 × 10 − 5 at 323.15 K). Interestingly, the solubility of pranlukast hemihydrate increases with a decrease in dielectric constant of the primary alcohols. The measured solubility data of pranlukast hemihydrate correlated well with the modified Apelblat equation. In addition, thermodynamic analysis indicated an endothermic and spontaneous dissolution behavior of pranlukast hemihydrate in the studied solvents. Therefore, these experimental solubilities and correlation equations can be useful in the purification/crystallization and formulation study of pranlukast hemihydrate in laboratories and related industries. [ABSTRACT FROM AUTHOR]

The solubility of 3-amino-1,2,4-triazole in ten organic solvents including ethanol, isopropanol, n -propanol, methanol, ethyl acetate, acetone, acetonitrile, 1,4-dioxane, N -methyl-2-pyrrolidone and 2-butanone was determined experimentally by the isothermal saturation method over a temperature range from T = 283.15 K to T = 318.15 K under 101.1 kPa. For the studied temperature range, the solubility of 3-amino-1,2,4-triazole in mole fraction in the solvents increased with a rise of temperature. On the whole, they obeyed the following order from high to low in different solvents: N -methyl-2-pyrrolidone > methanol > ethanol > n -propanol > (isopropanol, acetone) > 1,4-dioxane > 2-butanone > (ethyl acetate, acetonitrile). The determined solubility results of 3-amino-1,2,4-triazole in the solvents studied were correlated using the modified Apelblat equation, Buchowski–Ksiazaczak λh equation, Wilson model and NRTL model. The maximum values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 9.45 × 10 −4 and 2.16%, respectively. In general, the four thermodynamic models were all acceptable for describing the solubility behaviour of 3-amino-1,2,4-triazole in these solvents. Furthermore, the mixing properties including the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were acquired. The solution process of 3-amino-1,2,4-triazole was spontaneous and favourable in the selected solvents. The solubility values obtained and the thermodynamic studies would be very useful for optimizing the purification process of 3-amino-1,2,4-triazole. [ABSTRACT FROM AUTHOR]

This work measured the solubility of forms I and II of anticoagulant drug rivaroxaban in a series of organic solvents in which the solubility of form II was firstly reported as supplementary to the work of Zhang et al. [22]. A dynamic dissolution method was used to determine the solubility of both forms in acetonitrile, methyl acetate, acetone, 2-butanone, 3-pentanone and 2-hexanone from (273.15 to 318.15) K and in 1,4-dioxane from (288.15 to 333.15) K. The results showed that, the solubility of both forms generally increased with the temperature and decreased with an increase in the carbon number of ketones at the same temperature. The two forms were monotropically related and form II was the metastable form giving a higher solubility than form I. Meanwhile, such semiempirical thermodynamic models based on local composition concept as Wilson, nonrandom two-liquid (NRTL) and universal quasi chemical (UNIQUAC) equations with the correlation between model parameters and temperature were employed to model the studied solid-liquid equilibrium. It was found that UNIQUAC was the most appropriate model among the selected thermodynamic equations for the correlation of the solubility of rivaroxaban polymorphs in organic solvents. Finally, the apparent standard enthalpy change of dissolution was acquired from the experimental solubility data and the positive values of the apparent standard enthalpy change revealed that the dissolution of both forms of rivaroxaban in the selected solvents was an endothermic process. [ABSTRACT FROM AUTHOR]

The mole fraction solubility of paclobutrazol ((R,R) and (S,S)) mixture in nine pure solvents including ethanol, isopropanol, n -propanol, 1-butanol, ethyl acetate, toluene, acetone, acetonitrile and 1,4-dioxane was determined experimentally by using the isothermal saturation method over a temperature range from (278.15 to 318.15) K under atmospheric pressure. The mole fraction solubility of paclobutrazol in the selected solvents increased with a rise of temperature. In general, at a certain temperature, they decreased according to the following order in different solvents except for ethyl acetate: toluene > 1,4-dioxane > acetone > 1-butanol > n -propanol > ethanol > isopropanol > acetonitrile. The paclobutrazol solubility showed stronger dependency on temperature in ethyl acetate than in the other solvents. The solubility determined for paclobutrazol in the selected solvents was correlated with the modified Apelblat equation, λh equation, Wilson model and NRTL model. The maximum values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 3.98 × 10 −4 and 1.53%, respectively. On the whole, the four thermodynamic models were all acceptable for describing the systems of paclobutrazol in these solvents. Furthermore, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were obtained. The mixing process of paclobutrazol was spontaneous and exothermic in the solvents studied. The solubility determined and the thermodynamic properties derived should be very helpful for optimizing the purification process of paclobutrazol. [ABSTRACT FROM AUTHOR]