Abstract The equilibrium solubility and thermodynamic properties of busulfan in fifteen organic single solvents were reported. Solubility determinations were performed through the laser monitoring method at T = (278.15-323.15) K (except DMSO at 298.15-323.15 K) and p = 101.3 kPa. It can be found that the mole fraction solubility of busulfan increases apparently with the augmented experimental temperature. The solubility of busulfan in single solvents exhibits the following order from maximum to minimal at 303.15 K: NMP (4.870e-2) > DMSO (4.591e-2) > DMF (3.966e-2) > methyl acetate (4.502e-3) > 2-methoxyethanol (3.105e-3) > ethyl acetate (2.090e-3) > n-propyl acetate (1.367e-3) > 2-ethoxyethanol (1.280e-3) > n-butyl acetate (9.618e-4) > 2-propoxyethanol (6.930e-4) > 2-butoxyethanol (5.219 e-4) > methanol (3.787e-4) > ethanol (1.423e-4) > n-propanol (6.680e-5) > n-butanol (6.350e-5). The maximum value in busulfan solubility profile is related to DMSO at 323.15 K (x1 = 1.035 e-1) and the minimum one is obtained for n-butanol (6.800e-6, T =278.15 K). The results of using KAT-LSER model to study the solvent effect of busulfan solubility in fifteen single solvents show that solute-solvent interactions are principally attributed to the dipolarity/polarizability interaction and the hydrogen bonding basicity. And then, the determined solubility values of busulfan have been fitted to five widely used thermodynamic models, namely, λh, modified Apleblat, NRTL, NRTL-SAC and UNIQUAC models. The calculated results via the five models were all consistent with the solubility values, indicating that all models could provide high fitting accuracy. Moreover, according to the results of apparent thermodynamic properties calculated by Van’t Hoff equation, it can be stated that the dissolution process of busulfan in all selected solvents is recorded as an endothermic, non-spontaneous process driven by entropy.

中文翻译：

---

白消安在十五种纯溶剂中的固液相平衡：溶解度测定、溶剂效应、模型相关性和热力学分析

摘要 报道了白消安在十五种有机单一溶剂中的平衡溶解度和热力学性质。通过激光监测方法在 T = (278.15-323.15) K（298.15-323.15 K 的 DMSO 除外）和 p = 101.3 kPa 下进行溶解度测定。可以发现，随着实验温度的升高，白消安的摩尔分数溶解度明显增加。白消安在单一溶剂中的溶解度在 303.15 K 时从最大到最小显示以下顺序：NMP (4.870e-2) > DMSO (4.591e-2) > DMF (3.966e-2) > 乙酸甲酯 (4.502e-3) ) > 2-甲氧基乙醇 (3.105e-3) > 乙酸乙酯 (2.090e-3) > 乙酸正丙酯 (1.367e-3) > 2-乙氧基乙醇 (1.280e-3) > 乙酸正丁酯 (9.618e- 4) > 2-丙氧基乙醇 (6.930e-4) > 2-丁氧基乙醇 (5.219 e-4) > 甲醇 (3. 787e-4) > 乙醇 (1.423e-4) > 正丙醇 (6.680e-5) > 正丁醇 (6.350e-5)。白消安溶解度曲线的最大值与 323.15 K (x1 = 1.035 e-1) 的 DMSO 相关，最小值与正丁醇 (6.800e-6, T = 278.15 K) 相关。使用 KAT-LSER 模型研究白消安在 15 种单一溶剂中溶解度的溶剂效应的结果表明，溶质-溶剂相互作用主要归因于偶极/极化相互作用和氢键碱度。然后，将测定的白消安溶解度值拟合到五种广泛使用的热力学模型中，即 λh、修正的 Apleblat、NRTL、NRTL-SAC 和 UNIQUAC 模型。五个模型的计算结果均与溶解度值一致，表明所有模型均能提供较高的拟合精度。而且，