In this study, the solid–liquid phase equilibrium of the ternary adenine (C₅H₅N₅) + hydrogen peroxide (H₂O₂) + water (H₂O) system at 283.15 and 293.15 K under atmospheric pressure (p = 101.1 kPa) was determined using the isothermal saturation methodology. The solubility data of adenine in various concentrations of hydrogen peroxide solutions were determined, and two ternary phase diagrams were built using the wet residue method of Schreinemakers. At a certain temperature, two pure solids corresponding to pure adenine and pure C₅H₅N₅·H₂O₂ adduct appeared in each equilibrium system. As the temperature dropped, the saturated areas of pure C₅H₅N₅·H₂O₂ adduct and adenine increased. Under the same conditions, the saturated region of the C₅H₅N₅·H₂O₂ adduct was significantly larger than that of adenine. In addition, the C₅H₅N₅·H₂O₂ adduct produced based on the ternary phase diagram of C₅H₅N₅ + H₂O₂ + H₂O was characterized by infrared spectra, X-ray powder diffraction, thermogravimetry, and morphology. In addition, the influence of ethanol upon the solid–liquid phase equilibrium was investigated. Addition of ethanol increases the solubility of adenine and C₅H₅N₅·H₂O₂ adduct.

中文翻译：

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腺嘌呤 + 过氧化氢 + 水的三相平衡和腺嘌呤与过氧化氢加合物的表征

本研究中，三元腺嘌呤（C ₅ H ₅ N ₅）+过氧化氢（H ₂ O ₂）+水（H ₂ O）体系在大气压下283.15和293.15 K的固液相平衡（p = 101.1 kPa) 是使用等温饱和方法确定的。测定了腺嘌呤在不同浓度过氧化氢溶液中的溶解度数据，并利用Schreinemakers的湿残法建立了两个三元相图。在一定温度下，两种纯固体分别对应纯腺嘌呤和纯C ₅ H ₅ N ₅ ·H ₂ O ₂加合物出现在每个平衡系统中。随着温度的降低，纯C ₅ H ₅ N ₅ ·H ₂ O ₂加合物和腺嘌呤的饱和面积增加。在相同条件下，C ₅ H ₅ N ₅ ·H ₂ O ₂加合物的饱和区明显大于腺嘌呤。此外，根据C ₅ H ₅ N ₅ + H ₂三元相图生成的C ₅ H ₅ N ₅ ·H ₂ O _2加合物通过红外光谱、X 射线粉末衍射、热重分析和形貌对O ₂ + H _{2 O 进行了表征。}此外，研究了乙醇对固液相平衡的影响。添加乙醇增加了腺嘌呤和C ₅ H ₅ N ₅ ·H ₂ O ₂加合物的溶解度。