Pure Organic Solvents Research Articles

Optimization of a silicon-based microencapsulation technology of phase change material without organic solvents

Phase change microcapsules (MPCM) have significant advantages, such as fast thermal response and low leakage rate, which can be widely used in construction, textile, and electric power fields. However, the existing microcapsule preparation process has high costs and complicated steps, which limits its popularization and application. This paper reports a de-organic reform of the in-situ polymerization method for the fabrication of MPCM. The aqueous phase (solvent) consisted of pure deionized water and surfactant instead of conventional partial or pure organic solvents such as ethanol and acetamide. Taking the type and content of surfactant, homogenization speed, solvent ratio and core-shell ratio as the research variables, the optimal fabrication scheme of silicon-based MPCM in an alkaline environment was confirmed. The results showed that the Pa@SiO2 microcapsules prepared by pure inorganic solvents had great shape stability to prevent phase change material leakage and great temperature regulation performance when appropriate amount of hexadecyl trimethyl ammonium bromide was the surfactant and 3-Aminopropyltriethoxysilane was the silane coupling agent. More importantly, it has high heat storage capacity of 191.5 J/g due to its excellent encapsulation ratio of 76.4 %. Therefore, the fabrication method without organic solvent can simplify the fabrication process and greatly reduce the fabrication cost while ensuring excellent thermal properties of microcapsules, especially the outstanding heat storage capacity, which shows great application prospects in terms of microcapsule large-scale production.

Measurement and correlation of solubility of 9-fluorenone in 11 pure organic solvents from T = 283.15 to 323.15 K

In this work, the solubility data of 9-fluorenone in 11 pure solvents (methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, acetonitrile, ethyl formate, ethyl acetate, dimethyl sulfoxide, n-hexane) were measured by the gravimetric method from 278.15 K to 318.15 K under atmospheric pressure. The results showed that the solubility of 9-fluorenone in all tested solvents increased with the raised temperature. The solubility data were correlated by the modified Apelblat equation, λh model and NRTL (non-radom two fluid) model. The average relative deviation (ARD) correlated by three thermodynamic models in different solvents was all below 5%, which indicated that the three thermodynamic models fit the solubility data well. Furthermore, the mixing thermodynamic properties of 9-fluorenone in pure solvent systems were calculated via NRTL model. The results indicated the dissolution process of 9-fluorenone is spontaneous and entropically favorable. The solubility and the mixing thermodynamic properties provided in this paper would play an important role in industrial manufacture and follow-up operation of 9-fluorenone.

Equilibrium solubility of 6-propyl-2-thiouracil in nine pure solvents: Determination, correlation, Hansen solubility parameter and thermodynamic properties

Investigation upon the solid–liquid equilibrium on solubility data of 6-propyl-2-thiouracil (PLT) in pure organic solvents is essential for separation and purifying in industry process. In this work, PLT solubility in nine neat solvents was experimentally determined at 278.15 K–323.15 K under P = 0.1 MPa. These selected solvents were tetrahydrofuran(THF), acetone, acetonitrile,1-butanol,1-pentanol, 2-butanol, methyl acetate, ethyl acetate,1-propyl acetate, respectively. Experiment results showed that solubility was consistent with temperature and decreased according to the order: THF > acetone>1-butanol≈1-pentanol> 2-butanol > methyl acetate > ethyl acetate>1-propyl acetate > acetonitrile. Solvent effect and Hansen solubility parameter (HSP) were incited to explain dissolution rule on solute. Four thermodynamic models (modified Apelblat model, Van't model, λh model and NRTL model) were adopted to correlate PLT solubility and provide good correlations on basis of RD, ARD and RMSD. In addition, thermodynamic properties (ΔH°, ΔS° and ΔG°) of PLT dissolution process in pure solvents were discussed and proved to be endothermic, entropically driven and non-spontaneous process.

Simultaneous determination of triclosan，triclocarban and p-chloro-m-xylenol in disinfectant，personal care products and oiltment by nonaqueous capillary electrophoresis

Triclosan （TCS）， triclocarban （TCC）， and p-chloro-m-xylenol （PCMX） are some of the most widely used antibiotics because of their broad-spectrum and highly-efficient bactericidal effects. In the context of disinfection， the National Standard GB 38598-2020 stipulates that the contents of the effective ingredients present in a disinfectant must be specified， wherein their range must fall within 90%-110% of the specified central value. To ensure a suitable product quality， analysis by high performance liquid chromatography （HPLC） is recommended by both the GB/T 27947-2020 and GB/T 34856-2017. However， the results analyzed according to the National Standard method often exceed the declared contents， thereby indicating the necessity to establish a new method based on a completely different principle （e. g.， capillary electrophoresis）， especially since it was not possible to analyze TCS， TCC， and PCMX in a single injection using the National Standard method. Moreover， using this method， large amounts of methanol were consumed， which could be potentially harmful to both operators and the environment. In terms of their water solubilities， this decreases in the order of PCMX>TCS>TCC， wherein TCC is insoluble in water. As such， the use of nonaqueous capillary electrophoresis （NACE） based on running buffer solutions prepared in pure organic solvents （e. g.， methanol or acetonitrile） is necessary. In this paper， a new NACE approach combined with an ultraviolet detection method was developed for the simultaneous analysis of TCS， TCC， and PCMX in disinfectants， personal care products， and ointments. For this purpose， an uncoated fused silica capillary （20 cm×50 μm， total length=30.2 cm） was used as the separation column with a separation buffer composed of 14 mmol/L sodium borate， 2 g/L polyethylene glycol （PEG） 20000， and 0.5 mmol/L dodecyltrimethylammonium bromide （DTAB） in methanol. Following optimization of the separation parameters， the complete and simultaneous separation of TCS， TCC， and PCMX was achieved when the sample solution was prepared using 5 g/L PEG 20000 in methanol-acetonitrile （50∶50， v/v）. It was possible to directly inject the sample into the analysis system after a simple dilution with the sample medium， and no interference was observed in any of the sample electropherograms when a separation voltage and detection wavelength of -12 kV and 214 nm were employed， respectively. Furthermore， TCS， TCC， and PCMX showed good linear relationships with their corrected peak areas within a mass concentration range of 1-100 mg/L， and the correlation coefficients （r） were all greater than 0.99. Moreover， the limits of detection （LODs， S/N=3） and limits of quantification （LOQs， S/N=10） were determined to be 0.2 and 1 mg/L， respectively. The spiked recoveries ranged from 94.5% to 104.4% with relative standard deviations of ≤4.8% in all cases. Subsequently， the established method was used to analyze 31 commercial samples， including hand sanitizer， disinfectant， baby powder， and antibacterial cream. A comparative analysis of HPLC， the developed NACE method， and our previously reported micellar electrokinetic chromatographic （MEKC） method was also carried out for the quantitative determination of TCS， TCC， and PCMX. Although no statistically significant differences were observed among the three methods， the results determined for 16 out of the 31 samples did not match the claimed contents. These results therefore indicate the necessity to further control the compositions of disinfectant products. Our results indicate that the newly established NACE method can be an important alternative to HPLC for routine laboratory analyses， especially considering that it minimizes waste generation， requires only a simple sample pretreatment process， and exhibits a good selectivity to the target compounds. It is therefore hoped that the NACE method will be incorporated into the National Standard method in the near future.

Fluorescent material based on Al-MOF and phenazine groups for detection of water content in organic solvents

[Formula: see text]-MIL-101(Al) material containing phenazine groups, i.e. 1-metal-organic framework (MOF) has been prepared and characterized via FT-IR, PXRD, TGA, SEM and [Formula: see text] adsorption and desorption isotherm in this work. 1-MOF can exhibit emission peaks at 447 nm (in pure aqueous solvent) and 595 nm (in pure organic solvents) under 327 nm ultraviolet excitation, respectively. Based on this interesting feature, 1-MOF has been effectively used as a ratiometric fluorescent probe to detect water content in organic solvents. The luminescence color of 1-MOF changed obviously from red to blue with the increasing of water content in organic solvents, which can be observed by the naked eyes. The route to detect water content in organic solvents is fast, accurate and possessing great application potential.

Engineered living hydrogels enable efficient biocatalysis beyond just buffers

In the October issue of <i>Cell Reports Physical Science</i>, Gao and coworkers demonstrate smart engineered living hydrogels as a versatile platform for robust and tunable biocatalysis with improved tolerance of pure organic solvents.

Boosting Catalytic Selectivity through a Precise Spatial Control of Catalysts at Pickering Droplet Interfaces.

Exploration of new methodologies to tune catalytic selectivity is a long-sought goal in catalytic community. In this work, oil-water interfaces of Pickering emulsions are developed to effectively regulate catalytic selectivity of hydrogenation reactions, which was achieved via a precise control of the spatial distribution of metal nanoparticles at the droplet interfaces. It was found that Pd nanoparticles located in the inner interfacial layer of Pickering droplets exhibited a significantly enhanced selectivity for p-chloroaniline (up to 99.6%) in the hydrogenation of p-chloronitrobenzene in comparison to those in the outer interfacial layer (63.6%) in pure water (68.5%) or in pure organic solvents (46.8%). Experimental and theoretical investigations indicated that such a remarkable interfacial microregion-dependent catalytic selectivity was attributed to the microenvironments of the coexistence of water and organic solvent at the droplet interfaces, which could provide unique interfacial hydrogen-bonding interactions and solvation effects so as to alter the adsorption patterns of p-chloronitrobenzene and p-chloroaniline on the Pd nanoparticles, thereby avoiding the unwanted contact of C-Cl bonds with the metal surfaces. Our strategy of precise spatial control of catalysts at liquid-liquid interfaces and the unprecedented interfacial effect reported here not only provide new insights into the liquid-liquid interfacial reactions but also open an avenue to boost catalytic selectivity.

A comparative analysis of volumetric, viscometric and conductometric properties of Triethylmethylammonium Tetrafluoroborate (TEMABF4) and Tetraethylammonium Tetrafluoroborate (TEABF4) in pure propylene carbonate (PC) and binary aqueous propylene carbonate solvents

Electrolytes play a major role in electrochemical energy storage devices and specifically organic electrolytes are used predominantly over aqueous electrolytes due to wide electrochemical window, high energy density and efficiency. However, aqueous electrolytic systems for energy storage applications still need to be explored as these are non-flammable, environment friendly, non-toxic, carrying high ionic conductivity and low cost as compared to organic counterparts. In this study, an effort has been made in doing a comparative analysis of the physicochemical properties of Triethylmethylammonium Tetrafluoroborate (TEMABF4) and Tetraethylammonium Tetrafluoroborate (TEABF4) in pure propylene carbonate (PC) and binary aqueous mixtures of PC (0.01 &0.02 m) at different temperatures and concentrations. From this data, various volumetric, viscometric, and conductometric parameters have been calculated and the results obtained are analysed and compared in terms of solute–solute and solute–solvent interactions. From the analysis of thermo physical parameters, we have found that both the salts act as structure breaker in PC whereas structure maker in binary aqueous mixtures of PC (0.01 & 0.02 m). FTIR studies have also been done to see the intermolecular interactions and structural alterations. Furthermore, results from Cyclic Voltammetry (CV) studies suggested that a binary aqueous organic electrolytic system can also be a potential electrolytic system as its electrochemical window is comparable to that of pure electrolytic organic solvents.

Porous Carbon Sponge from White-Rot Fungus Phanerochaete chrysosporium for the Removal of Oils and Organic Solvents.

Oil leakage incidentally occurs and leads to environmental disasters. Because of their porous and hydrophobic characteristics, graphene sponges are often studied as an oil adsorbent to repair oil spills at sea. Graphene materials are very expensive, and their biological toxicity has been given serious concerns; however, the easier preparation and eco-friendly, biomass-derived porous carbon materials can be used as an alternative to graphene materials. In this study, we prepared a porous carbon sponge (PCS) for oil and organic solvent removal by carbonizing white-rot fungus Phanerochaete chrysosporium, a fast-growing microorganism for the production of lignin-degrading enzymes and the environmental remediation. P. chrysosporium fungus balls were converted into black PCS by carbonization at high temperatures, where PCS was light (density of 56 g/L), hydrophobic (contact angle of 115°) and porous. According to the results of BET and XPS analysis, the surface area of PCS was 14.43 m2/g, and the carbon in PCS is mainly sp2 carbon. PCS could adsorb pure oils and organic solvents within seconds. The adsorption capacities of PCS were 20.7 g/g for gasoline, 30.1 g/g for peanut oil, 27.7 g/g for toluene, 18.5 g/g for dodecane, 32.5 g/g for chloroform, 27.1 g/g for tetrahydrofuran, 23.7 g/g for acetone and 13.7 g/g for ethanol. According to the reusability study, there was no obvious capacity loss after recycling up to 10 cycles. Our results indicated that white-rot fungi could be adopted as a cheap carbon resource for oil and organic solvent removal.

Lesser mealworm (Alphitobius diaperinus L.) larvae oils extracted by pure and binary mixed organic solvents: Physicochemical and antioxidant properties, fatty acid composition, and lipid quality indices

Insect oil is one of the most sustainable lipid sources with remarkable health effects. Herein, the type of organic solvents (i.e., n-hexane, ethanol, and isopropanol) and their binary mixtures was evaluated based on the quantity (e.g., yield extraction) and quality (e.g., bioactive compounds, thermal stability, DPPH scavenging rate, fatty acid profile, and nutritional indices) of lesser mealworm oils. The oils extracted by ethanol/isopropanol and ethanol/n-hexane significantly showed the highest extraction yield and efficiency, lightness, accelerated thermal stability, phenolics, tocopherols, vitamin D, campesterol, β-sitosterol, phosphatidylinositol and phosphatic acid, linoleic acid, and hypocholesterolemic/hypercholesterolemic ratio, while these organic mixtures meaningfully extracted lipids with the lowest peroxide value, free fatty acid, and atherogenicity and thrombogenicity indices. These solvents compared to pure ones could dissolve membrane and internal lipids with the complete disintegration of external structures. The ethanol/isopropanol mixture would be a promising solvent for n-hexane substitution to extract this oil on an industrial scale.

Measurement and Correlation of the Solubility of Salbutamol in Ten Pure and Binary Mixed Organic Solvents from T = 283.15–328.15 K

In this study, the gravimetric method was used to measure the solubility of salbutamol in ten pure and binary mixed organic solvents, including methanol, isobutanol, ethanol, isopropyl alcohol, 1-propanol, 1-butanol, 2-butanol, methyl acetate, ethyl acetate, acetone, and methanol + 2-butanol, in the range of 283.15–328.15 K at atmospheric pressure. The solubility curve showed an increasing trend with an increase in temperature. In addition, the modified Apelblat model, λh model, van’t Hoff, van’t Hoff–Jouyban–Acree, and Apelblat–Jouyban–Acree model were used to fit the experimental data, and the fitting results were satisfactory. Compared with other models, the Apelblat model showed the highest agreement with the experimental data. This work provides important data for the synthesis and purification of salbutamol.

Solubility measurement and correlation of 2-aminoterephthalic acid in eight alcoholic solvents at different temperatures

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 (Δ0Gsol, Δ0Hsol and Δ0Ssol) 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.

Solubility measurement, correlation and thermodynamic properties of 9H-thioxanthen-9-one in twelve mono organic solvents from 292.15 K to 335.95 K

The 9H-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.

Solubility, solvent effect, preferential solvation and DFT computations of 5-nitrosalicylic acid in several aqueous blends

The purpose of this contribution was to investigate the solubility, computational techniques, solvent effect, and preferential solvation of 5-nitrosalicylic acid in blended solvents of acetonitrile/N,N-dimethylformamide(DMF)/methanol/n-propanol + water. Visualizing regions of weak contact between 5-nitrosalicylic acid and solvent using an independent gradient model based on Hirshfeld partitioning (IGMH), and providing a quantitative study for the molecule’s electrostatic characteristics using a molecular surface research and Hirshfeld surface analysis were carried out. All equilibrium solubility measurements were performed using a shake-flask technique at temperatures from 278.15 to 323.15 K and pressure of 101.2 kPa. For each blends studied, the lowest solubility was observed at 278.15 K in water and the highest at 323.15 K in pure organic solvent. Using linear solvation energy relationships, the effect of molecular interactions on solubility variation was studied, revealing that the solubility parameter and dipolarity-polarizability played a substantial impact in solubility variation. By correlating the derived equilibrium solubilities with the Jouyban-Acree, modified Apelblat-Jouyban-Acree, and van't Hoff–Jouyban–Acree models, a maximum relative average deviation of 4.01 percent was obtained. Quantitative investigation of the solvation behavior of 5-nitrosalicylic acid by solvent species was conducted using the method of inverse Kirkwood–Buff integrals. Positive values of the preferential solvation parameter in acetonitrile/DMF/methanol/n-propanol-middle and -rich blended systems indicated that acetonitrile/DMF/methanol/n-propanol solvated 5-nitrosalicylic acid preferentially. In the above composition ranges, it is hypothesized that 5-nitrosalicylic acid interacts with nearby methanol/DMF/n-propanol molecules as a Lewis acid, whereas solvation by acetonitrile is due to the polarization effect.

Solubility, aggregation and stability of Amphotericin B drug in pure organic solvents: Thermodynamic analysis and solid form characterization

The solubility of amphotericin B (AmB) has been studied between temperatures of 298–343 K in a range of pure organic solvents including methanol, ethanol, isopropanol, butanol, acetone, tetrahydrofuran, and 1,4-dioxane. The initial solid form used in solubility determinations has been characterized by a series of techniques including powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and Raman spectroscopy, thermogravimetric analysis and differential scanning calorimetry. Pure AmB melts at 444.5 K with an associated enthalpy of fusion of 177.2 kJ/mol. The equilibrated solids in suspension have been characterized by SEM and PXRD and additionally, the equilibrated saturated solutions have been characterized by in-situ UV–vis to probe the saturation and the aggregation state of AmB. In the explored solvents, in terms of mass ratio, the solubility has been found to be remarkably low, decreasing in the order: ethanol > tetrahydrofuran > butanol ≃ 1,4-dioxane ≃ isopropanol > acetone. The relative order of solubility obtained in the alcohols correlates well with their polarity, revealing important interactions of the solvents’ hydroxyl group with the polyol chain and the micosamine sugar carboxylic moiety of amphotericin B. Except in dioxane and isopropanol, the obtained Van’t Hoff enthalpies of solution reveal an inverse proportionality to the experimental molar fraction solubility values obtained experimentally, indicating a larger energy requirement to solvate AmB molecules. Aggregation of AmB in the equilibrated solutions was not detected in any of the solvents studied yet HPLC analyses revealed that the API degraded in methanol during the equilibration time for the solubility determinations.

Engineered living hydrogels for robust biocatalysis in pure organic solvents

Engineered living hydrogels that can protect cells from harsh environments have achieved preliminary successes in biomedicine and environmental remediation. However, their biocatalytic applications in pure organic solvents have not been explored. Here, living hydrogels were engineered by integrating genetically modified Escherichia coli cells into alginate hydrogels for robust biocatalysis in pure organic solvents. The biocompatible hydrogels could not only support cell growth and diminish cell escape but could also act as protective matrices to improve organic solvent tolerance, thereby prolonging catalytic activity of whole-cell biocatalysts. Moreover, the influence of hydrogel microenvironments on biocatalytic efficiency was thoroughly investigated. Importantly, the versatility of engineered living hydrogels paves the way to achieve robust biocatalytic efficiency in a variety of pure organic co-solvents. Overall, we are able to engineer living hydrogels for regio-selective synthesis in pure organic solvents, which may be particularly useful for the innovation of living hydrogels in biocatalysis. • Living hydrogels are engineered by integrating microbial cells and alginate hydrogels • Hydrogel microenvironments modulate catalytic efficiency of engineered living hydrogels • Engineered living hydrogels enable improved solvent tolerance in pure organic solvents • The versatility of engineered living hydrogels for robust biocatalysis is verified A versatile strategy to improve the organic solvent tolerance of whole-cell biocatalysts is highly demanded. Gao et al. design engineered living hydrogels using genetically modified microbial cells for improved organic solvent tolerance and robust biocatalysis in pure organic solvents.

Solubility Determination, Computational Methodologies, and Preferential Solvation of 3-Nitro-1,2,4-triazol-5-one in Several Solvent Blends

This work sought to explore the solubility, computational methodologies, and preferential solvation of 3-nitro-1,2,4-triazol-5-one (NTO) in methanol/ethanol + ethyl acetate and methanol/isopropanol + water blends. Evaluation of equilibrium solubility was performed by an isothermal dissolution technique under 101.2 kPa ranging from 278.15 to 318.15 K. The lowest solubility magnitude was discovered in pure water at 278.15 K, while the greatest one was obtained in pure organic solvents at 318.15 K. The solubility data of NTO was interpreted using the Hansen solubility parameter. To correlate the determined solubilities, modified Wilson, Jouyban–Acree, van’t Hoff–Jouyban–Acree, and Apelblat models were utilized, producing the highest relative average deviation of 2.53%. A quantitative examination of the solvation behavior of NTO by solvent species was carried out using the inverse Kirkwood–Buff integrals. Positive solvation parameters in methanol/isopropanol/ethanol-rich blends showed that methanol/isopropanol/ethanol solvated NTO preferentially.

Development of an Automatable Affinity Purification Process for DNA-Encoded Chemistry.

DNA-encoded library technologies require high-throughput, compatible, and well automatable platforms for chemistry development, building block rehearsal, and library synthesis. An affinity-based process using Watson–Crick interactions was developed that enables purification of DNA-tagged compounds from complex reaction mixtures. The purification relies on a single-stranded DNA-oligonucleotide, called capture strand, which was covalently coupled to an agarose matrix and to which a DNA-compound conjugate from a DNA-encoded library (DEL) reaction can be reversibly annealed to. The thus-formed DNA duplex tolerated surprisingly stringent washing conditions with multiple solvents to remove excess reactants and reagents. The tolerated solvents included aqueous buffers, aqueous EDTA solutions to remove metal ions, aqueous mixtures of organic solvents, and even pure organic solvents. The purified DNA-conjugate was eluted with aqueous ammonia and could be used for reaction analysis or for instance in DNA-encoded library synthesis. The lab equipment for purification was tailored for automation with open-source hardware and constructed by 3D printing.

Solubility measurement and correlation of 2-chlorothioxanthone (CTX) in twelve mono organic solvents

• Solubility of 2-chlorothioxanthone in twelve pure solvents was determined. • Solubility was correlated by Apelblat, λh , Wilson and NRTL model. • Thermodynamic properties of mixing process were also discussed. 2-Chlorothioxanthone (CTX) is one of the most widely used commercial photoinitiators for pharmaceutical preparations as well as for preparations of synthetic resins. The solubility of CTX in twelve pure organic solvents was measured using the gravimetric method from 287.55 to 335.95 K at normal pressure. The results shows that the solubility of CTX in all the solvents increases as temperature rising. The melting point and fusion enthalpy of CTX were measured with differential scanning calorimeter. The experimental solubility data were correlated with four thermodynamic models, including modified Apelblat equation, λh equation, Wilson equation and NRTL equation. The best correlation results were found with modified Apelblat equation and NRTL equation. The mixing thermodynamic functions (Gibbs free energy, enthalpy and entropy) were calculated based on the Wilson equation. The results showed that the entire mixing process is spontaneous.

Solubility Measurement and Thermodynamic Model Correlation of Baclofen in 12 Pure Organic Solvents

Solubility Measurement and Thermodynamic Model Correlation of Baclofen in 12 Pure Organic Solvents