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• The differences in interaction strength between AOEMIMTFSI and DMSO/CH 3 OH/CH 3 CN are described in detail. • The changes of hydrogen bonding interactions was unveiled. • Several complexes were assigned by excess spectra. Scientific research has witnessed an increasing fascination with ester-functionalized ionic liquids in recent years. These ester-functionalized ionic liquids are particularly attractive due to their superior biodegradability and potential applications, which surpass those of traditional ionic liquids. In actual use, it is common to blend these ionic liquids with co-solvents. However, there is currently a lack of research on the structures and interaction mechanisms of these mixtures. In this work, the hydrogen bonding interactions and microstructures of 1-acetoxyethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (AOEMIMTFSI) with various polar co-solvents (DMSO, CH 3 OH, CH 3 CN) were researched by combining infrared experiments and DFT calculations. The finding are as follows: (1) O atom in [TFSI]− primary interacts with C2−H in [AOEMIM]+, while the O or N atom in the co-solvents (DMSO, CH 3 OH, CH 3 CN) primarily interact with C4,5−H in [AOEMIM]+. (2) With the addition of co-solvents (DMSO‑ d 6 , CD 3 OD or CD 3 CN), the hydrogen bonding interactions associated with the v (imidazolium C−H) in the AOEMIMTFSI−DMSO‑ d 6 /CD 3 OD/CD 3 CN systems are strengthened. (3) The hydrogen bonding interactions between AOEMIMTFSI and DMSO are the strongest, followed by those between AOEMIMTFSI and CH 3 OH, while the hydrogen bonding interactions between AOEMIMTFSI and CH 3 CN are the weakest. (4) 2[AOEMIM]+[TFSI]−, 2[AOEMIM]+[TFSI]−−co-solvent, [AOEMIM]+[TFSI]−−co-solvent and [AOEMIM]+−co-solvent complexes were assigned through the analysis of excess spectra. [ABSTRACT FROM AUTHOR]

• The fundamental mechanism of azeotrope breaking in DMC–ethanol by an IL was uncovered. • FTIR and DFT were combined to analyse the v (aromatic C–H) and v (O–D) regions. • Interaction strength and complexes between different components were revealed. • The interactions of IL–ethanol were stronger and changed the mixture's volatility. • The IL can break the DMC–ethanol complex (cause of azeotropy). Owing to their outstanding properties, ionic liquids (ILs) have been increasingly applied as entrainers to separate alcohol azeotrope systems in extractive distillation. Fundamental studies on the mechanism of azeotrope breaking are essential for the better use of ILs; however, they are not often reported. To reveal the intrinsic cause of azeotrope breaking by an IL entrainer, on this work, the microstructure features of IL–azeotrope systems were investigated using FTIR and DFT calculations. 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][Tf 2 N]) and the azeotrope systems dimethyl carbonate (DMC) and ethanol were selected. The v (aromatic C–H) region of the imidazolium cation was analysed first to distinguish the relative interaction strength between the IL and ethanol/DMC. The v (O–D) region of ethanol was applied to identify the interaction complexes in different mixtures and estimate the relative interaction strength between ethanol and the IL/DMC. Combined with DFT calculations, it was found that interactions between [BMIM][Tf 2 N] and ethanol were stronger than those between [BMIM][Tf 2 N] and DMC, which could influence the relative vapour pressure of the two constituents, thus breaking the azeotrope. The interactions between ethanol and the IL were stronger than those between ethanol and DMC. Thus, the addition of the IL could break the interaction complex of DMC–ethanol, which is the cause of azeotropy in the DMC–ethanol system. When x (IL) was larger than 0.170, the entire DMC–ethanol complex disappeared accompanied with the eliminated of the azeotrope. [ABSTRACT FROM AUTHOR]

Abstract The solubility of cyromazine in three binary solvent mixtures (acetic acid + water, propanoic acid + water, ethylene glycol + water) were measured by a gravimetric method from 278.15 K to 333.15 K under atmospheric pressure. The experimental results reveal that the mole fraction solubility of cyromazine increased with the increase of temperature in the three solvents. The Apelblat equation, the λh equation, the general single model (GSM) equation and the modified Jouyban-Acree model equation were all applied to correlate the experimental solubility of cyromazine well. Moreover, the dissolution thermodynamic properties: Δ sol H 0 (the apparent standard enthalpy change), Δ sol S 0 (the apparent standard entropy change), Δ sol G 0 (the apparent standard Gibbs energy change), ζ H (relative contribution of enthalpy) and ζ TS (relative contribution of entropy) of the dissolution of cyromazine in the selected solvents were calculated. The positive values of Δ sol H 0, Δ sol G 0, ζ H ≥ 0.5984 and ζ TS ≤ 0.4016 indicated that the dissolution of cyromazine in the three binary solvents was enthalpy-driving and endothermic process. The experimental solubility of cyromazine in this work can provide good guidance and fundamental data for the crystallization, purification and application of cyromazine. Highlights • The solubility of cyromazine in three binary solvent mixtures were experimentally determined. • The experimental solubility data of cyromazine were correlated by four thermodynamic models. • The dissolution thermodynamic properties of cyromazine in the selected solvents were discussed. [ABSTRACT FROM AUTHOR]

• The differences in interaction strength between [EMIM]+ and [TFSI]−/[SCN]− are described in detail. • With the increase of x (EMIMTFSI), and the tendency to aggregate between [TFSI]−/[SCN]− and [EMIM]+ was enhanced. • Several complexes were assigned by excess spectra. Recently, ionic liquid mixtures have been widely studied and successfully applied in many fields. However, the basic knowledge of their molecular interactions is not yet fully understood. In this work, the structural characteristics and interaction mechanisms of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIMTFSI) and 1-ethyl-3-methylimidazolium thiocyanate (EMIMSCN) mixtures in different proportions were researched by combining theoretical and experimental methods. The conclusions drawn are summarized as follows: (1) The main interaction sites for [EMIM]+, [TFSI]− and [SCN]− are C2−H, O and N atoms, respectively. (2) With the increase in x (EMIMTFSI), the hydrogen bonding interactions in the EMIMTFSI−EMIMSCN system were weakened, and the tendency to aggregate between two anions ([TFSI]−, [SCN]−) and [EMIM]+ was enhanced. (3) The interaction between [EMIM]+ and [SCN]− is stronger than that between [EMIM]+ and [TFSI]−. The order of diffusion speed is [EMIM]+ > [TFSI]− > [SCN]−. (4) New forming EMIMTFSI and EMIMSCN interacting complexes were assigned by excess spectra. [ABSTRACT FROM AUTHOR]

• The changes of hydrogen bonding interactions was unveiled. • All the hydrogen bonds are in the category of weak hydrogen bonds. • Microheterogeneity of the liquid mixtures was characterized in detail. • Several complexes were identified in the mixing process. A recent focus in the ionic liquid field is to mix two (or more) ionic liquids to expand the available properties. In this work, the interactions and structural properties of 1-ethyl-3-methylimidazolium bis(trifluoromethyl)sulfonylimide (EMIMTFSI) and 1-ethyl-3-methylimidazolium dicyanamide (EMIMDCA) mixtures were investigated by employing multiple experimental methods and DFT calculations. Microheterogeneity of the liquid mixtures was characterized in detail and four complexes or clusters were identified, i.e. 2EMIMTFSI, 2EMIMDCA, 2EMIMTFSI-[DCA]− and 2EMIMDCA-[TFSI]−. Hydrogen bonding interactions between cations and anions were found to be ubiquitous but all in the category of weak interactions. The main interaction sites for [EMIM]+, [TFSI]−, and [DCA]− were found to be C2−H, O/N atoms, and N (in C≡N). This work adds value to an in-depth understanding of the microstructures and molecular interactions in the specified ionic liquid mixtures and would shed light to the general understanding of the ionic liquid systems as a whole. [ABSTRACT FROM AUTHOR]

Some citations were missed in our published paper [J.Mol.Liq. 272 (2018) 158–169]. The solubility of cyromazine in pure solvent (water) between 283.15 K and 323.15 K, the solubility of cyromazine in pure solvent (propanoic acid) between 278.15 K and 318.15 K, the solubility of cyromazine in pure solvent (acetic acid) between 293.15 K and 333.15 K has been determined in our previous work [Fluid Phase Equilib. 475 (2018) 77–88], it was our negligence that we forgot to provide the corresponding reference in the published work [J.Mol.Liq. 272 (2018) 158–169], besides, the citations about the melting properties (melting point T m and fusion enthalpy Δ fus H) of cyromazine also needed to provide. • The references were missed in our previous work. • The erratum provided the corresponding citations. • The erratum improved the quality of our previous work. [ABSTRACT FROM AUTHOR]

In this work, by using laser dynamic isothermal method, the solubilization behavior and thermodynamics of capecitabine solubility in the binary mixtures of n-hexane + ethyl acetate and n-heptane + ethyl acetate from (278.15 to 323.15) K were measured under atmospheric pressure. The measured results showed that the experimental solubility of capecitabine increased non-linearly with increasing temperature and ethyl acetate content (w 1) in the studied mixture solvents. Six cosolvency mathematical models including the modified Apelblat equation, combined nearly ideal binary solvent/Redlich-Kister (CNIBS/R-K) equation, Wilson model, non-random two liquid (NRTL) model, UNIQUAC model, and the modified Jouyban-Acree-van't Hoff model were fitted to the experimental results. The maximum relative average deviation (ARD) was 0.27, the maximum root-mean-square deviation (RMSD) was 0.0007. The order of the relative average deviation (ARD) of the six cosolvency mathematical models is CNIBS/R-K > modified Jouyban-Acree-van't Hoff > NRTL > Wilson > modified Apelblat > UNIQUAC. Basically speaking, the measured solubility data in this study can be well correlated with the six thermodynamic models, while the modified Jouyban-Acree-van't Hoff model allowed the calculation of solubility of capecitabine at an arbitrary mixture composition and temperature in the studied binary solvent mixtures composition and temperature. Moreover, apparent thermodynamic properties of capecitabine dissolution process in the investigated mixed solvents including entropy, enthalpy and Gibbs free energy were computed using van't Hoff and Gibbs equations. Besides, the logarithm of activity coefficient of capecitabine (lnγ 1) in the studied saturated solutions were also calculated with the NRTL model, UNIQUAC model, and Wilson model, respectively. The positive values of lnγ 1 means that the repulsive interactions exist between capecitabine and the corresponding mixture solvents, and the solutions system positively deviate from Raoult's law. This work can give fundamental data for the crystallization and purification of capecitabine from ethyl acetate. • The solubility of capecitabine in the binary mixtures were measure by the laser dynamic isothermal method. • The solubility data of capecitabine were corrected by the six thermodynamic equation. • The dissolution behavior of capecitabine in the mixture ternary solutions was studied. [ABSTRACT FROM AUTHOR]

In order to deal with the increasingly serious water pollution caused by dye wastewater, a novel sulfonic acid-modified polyacrylamide magnetic composite (Fe 3 O 4 @SiO 2 /P(AM-AMPS)) was facilely prepared by crosslink reaction. The physicochemical properties and adsorption performances of Fe 3 O 4 @SiO 2 /P(AM-AMPS) were systematically studied by different characterization techniques and a series of batch experiments, respectively. It was found that the adsorption capacities of Fe 3 O 4 @SiO 2 /P(AM-AMPS) towards cationic dyes crystal violet (CV) and methylene blue (MB) were largely enhanced than those of silica-coated Fe 3 O 4 (Fe 3 O 4 @SiO 2) and maintained at relatively high levels in a wide pH range, due to the three-dimensional network structure and abundant functional groups of modified polyacrylamide. Besides, owing to the introduction of Fe 3 O 4 @SiO 2 , Fe 3 O 4 @SiO 2 /P(AM-AMPS) presented a unique magnetic property that helped it to be rapidly separated from water in a magnetic field. The maximum adsorption capacities of Fe 3 O 4 @SiO 2 /P(AM-AMPS) were 2106.37 mg g−1 for CV removal and 1462.34 mg g−1 for MB removal at 298.15 K, much higher than those of other reported magnetic composites. Furthermore, Fe 3 O 4 @SiO 2 /P(AM-AMPS) was effectively regenerated with HCl solution and the regeneration rates were higher than 97% and 80% for CV and MB removal after five adsorption-desorption cycles, respectively. With its excellent adsorption capacity, wide pH applicability, high separation speed, and satisfactory regeneration ability, Fe 3 O 4 @SiO 2 /P(AM-AMPS) was expected to become a promising adsorbent in the purification of cationic dye wastewater. Unlabelled Image • Novel PAM-based magnetic composite was facilely prepared by crosslink reaction. • Fe 3 O 4 @SiO 2 /P(AM-AMPS) presented a wide pH applicability for cationic dyes removal. • The maximum adsorption capacities were 2106 mg g−1 for CV and 1462 mg g−1 for MB. • The superior adsorption ability was attributed to multiple adsorption mechanisms. • Unique magnetism and good reusability facilitated its practical application. [ABSTRACT FROM AUTHOR]

In this work, solubility of cis-5-norbornene-exo-2,3-dicarboxylic anhydride (himic anhydride) in binary solvents of (1,4-dioxane, DMF, NMP + ethanol) was experimentally determined by the gravimetric method ranged from 278.15 K to 323.15 K under 0.1 MPa. It was found that solubility of himic anhydride increased with elevating temperature while decreased as the mass fraction of ethanol increased. Solubility order of himic anhydride in three binary solvents was interpreted by comparing the interaction energy (E inter) between solute and binary solvents based on density function theory (DFT). Experimental solubility in binary solvents was correlated by the Two-Suffix Margules, NRTL, Wilson, uniquac and Jouyban-Acree-modified Apelblat (J-A-A) model. The Wilson, NRTL, uniquac and Two-Suffix Margules model are suitable to correlate the experimental solubility. Moreover, thermodynamic properties of dissolution process (Δ dis G , Δ dis S , Δ dis H , Δ mix G , Δ mix S , Δ mix H , H 1 E , ∞ , ln γ 1 and ln γ 1 ∞) were calculated by the Wilson equation. The dissolution process and mixing process of himic anhydride in selected binary solvents are entropy-positive. • Solubility of himic anhydride in three binary solvents was experimentally determined. • Molecular simulation was applied to explain the solubility behavior. • Thermodynamic modeling was realized by the Two-Suffix Margules, NRTL, Wilson, uniquac and J-A-A model. [ABSTRACT FROM AUTHOR]

Solubility of cis-5-norbornene-endo-2,3-dicarboxylic anhydride (carbic anhydride) in fourteen pure solvents including methyl acetate (MAC), ethyl acetate (EAC), n-propyl acetate (NPAC), isopropyl acetate (IPAC), n-butyl acetate (NBAC), n-amyl acetate (NAAC), isoamyl acetate (IAAC), hexyl acetate (HAC), octyl acetate (OAC), ethanol (EtOH), 1,4-dioxane, 1-methyl-2-pyrrolidinone (NMP), acetone, N , N -dimethylformamide (DMF) and three binary solvents of (DMF + EtOH), (1,4-dioxane + EtOH) and (EtAC + EtOH) with various mass fractions was experimentally studied at various temperatures under 0.1 MPa. The results showed that solubility of carbic anhydride increased with the increasing temperature in all pure/binary solvents and decreased with the increasing mass fractions of ethanol in binary solvents. The Hansen solubility parameter was used for explaining the solubility order of carbic anhydride in selected solvents. Solubility of carbic anhydride in pure solvents was correlated by van't Hoff equation, modified Apelblat equation, and λh equation. Experimental solubility of carbic anhydride in binary solvents was correlated by Jouyban-Acree model, Jouyban-Acree-modified Apelblat model, Jouyban-Acree-van't Hoff model, Sun model and Ma model. Moreover, thermodynamic properties of solutions were calculated by the van't Hoff analysis. The dissolution process was always endothermal and entropy-driven. • Solubility of carbic anhydride in pure and binary solvents was determined. • Experimental solubility was correlated by modified Apelblat, λh, van't Hoff, J-A, J-A-A, J-A-V, Sun and Ma model. • Hansen solubility parameter was used for explaining the solubility behavior. • Thermodynamic properties of solutions in this work were also discussed. [ABSTRACT FROM AUTHOR]