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• The solubility of Musk ambrette in single and binary solvents was determined. • The evaluation model for the relationship between solubility and temperature has been established. • The correspondence between solubility and the HSP, π , α , β , and CED of the solvents were discussed. • Molecular simulation was used to analyze the dissolution behavior of Musk ambrette. The solubility of Musk ambrette in i-propanol (IPA), i-butanol (IBA), n-heptane (HPT), n-hexane (HX), cyclohexane (CYH), methyl acetate (MAC), ethyl acetate (EAC), acetone (ACE), IPA + ACE at 278.15 K to 318.15 K was determined. The mole fraction solubility of Musk ambrette in pure IPA at the temperature of 298.15 K were found to be 0.9492 × 10-2 mol·mol−1. The difference is that the solubility of Musk ambrette in ACE reaches 0.2257 mol·mol−1, which is much higher than the solvent mentioned above. The strong intermolecular hydrogen bonding formed by IPA resulted in its lowest solvation capacity for Musk ambrette. In addition, to further investigate the solubility pattern of Musk ambrette, we used 8 models (Van't Hoff, modified Apelblat, Buchowski-Ksiazczak, Yaws, NRTL, Wilson, Jouyban-Acree and Sun model) to fit and obtain a general equation for solubility versus temperature. These results yielded a large amount of statistically significant data. Comparisons revealed that the modified Apelblat and Yaws equation showed the least deviation in forecasting solubility variations with temperature. Meanwhile, we proved that the dissolution of Musk ambrette is a heat-absorbing entropy increasing process by Van't Hoff equation calculation. Δ sol G o for the 12 solvents is in the following order: ACE < MAC < EAC < w = 0.2007 < w = 0.4025 < w = 0.6076 < CYH < w = 0.8070 < HPT < HX < IBA < IPA. Δ sol G o is smaller the easier it dissolves, which is consistent with the law of dissolution. Secondly, we performed thermal analysis and X-ray diffraction tests on Musk ambrette crystals prepared in different solvents, which showed that none of the several systems investigated led to the creation of new crystalline forms or solvatoids, further confirming the suitability of the solvents. Besides, we discuss the correspondence between solubility and the HSP, π , α , β , and CED of the solvents and thus tentatively confirm the significant influence of the solvent properties on solubility. The principle of similarity and compatibility is satisfied for most of the solvents. In particular, the CED values of the larger solvents were not favorable for the solubilization of Musk ambrette. We also analyzed the molecular surface electrostatic potential of Musk ambrette by visualization techniques. Finally, IPA and ACE and their binary solution systems were analyzed by molecular dynamics simulations. The effect of solvent intermolecular interactions on the solubilization pattern was discussed. It was further confirmed that weak interactions of solvent molecules contribute more to the dissolution of Musk ambrette. These findings suggest that the prediction of solvent solubility can be initially achieved by molecular simulation techniques. Undoubtedly, this study will furnish a valuable information for the purification of Musk ambrette. [ABSTRACT FROM AUTHOR]

[Display omitted] • The solubility of musk amberette in single and binary solvents was determined. • Different thermodynamics models were used to correlate the solubility data. • Thermodynamic properties of musk amberette solution were calculated. • The effects of solvent properties and Hansen solubility parameters on solvent solubility were discussed. • Molecular simulation was used to analyze the dissolution behavior of musk amberette. The solubility of 4- tert -Butyl-2, 6-dinitro-3-methoxytoluene (musk amberette) in methanol, ethanol, n-propanol, n-butanol, acetonitrile, N, N-dimethylformamide, N, N-dimethylacetamide, tetrahydrofuran and methanol + tetrahydrofuran at 278.15 K to 318.15 K were determined. All measurement data obtained good results by merging Van't Hoff, modified Apelblat, λh , Yaws, NRTL, Wilson, Jouyban-Acree and Sun model. The deviation analysis between fitting values and experimental values indicates that the Yaws model was more effectively in fitting the solubility of musk amberette. In addition, the Δ sol H °, Δ sol G °, Δ sol S ° of musk amberette solution were discussed by Van't Hoff equation. Their fruits implied that the dissolution of musk amberette is found to be accompanied by heat absorption and entropy gain processes. This is consistent with the positive slope of the T- x 1 curve, which means that high temperature is advantage for the continued dissolution of musk amberette. In contrast, the presence of strong hydrogen bonds between alcohol solvents results in their lowest solubility for musk amberette. As an important task, the melting performance and crystal structure of musk amber were tested through instruments. The same characteristics exclude the presence of solvates or polymorphs. Finally, molecular visualization analysis was used to summarize the interatomic interactions within the crystal of musk amberette. The relationship between HSP, π , α , β , CED and their ability to dissolve musk amberette was discussed. It has been proven that high CED of the solvent is the main obstacle to the dissolution of musk amberette. The interaction between the O atom of musk amberette and hydroxyl H atom of alcohol in binary mixed solutions was obtained through molecular dynamics. Further, elucidated the relationship between mixed solvents and solubility. In summary, these studies will provide strong guidance for the upgrading of musk amberette production processes. [ABSTRACT FROM AUTHOR]