A semiflow type apparatus for solid solute solubility measurement was constructed to investigate the solubility of isomers of methylsalicylic acid (MSA) in supercritical carbon dioxide (ScCO₂). The solubility of salicylic acid in ScCO₂ was measured in seeking to validate the reliability of the apparatus and the experimental procedure. The solubility of three MSA isomers, 3-MSA, 4-MSA, and 5-MSA, were measured at 308.2, 318.2, and 328.2 K, respectively, over a pressure range of 9–18.5 MPa. The results showed that the solubility of MSA isomers was within the range of 8.3 × 10^–6 and 5.9 × 10^–4. These newly measured solubility data were correlated by four semiempirical models; satisfactory correlation results were obtained with the average absolute relative deviation in solubility within 8.17%. The consistency of the solubility data was confirmed by the good correlation results with the Chrastil and Méndez-Santiago and Teja models.

中文翻译：

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甲基水杨酸异构体在超临界二氧化碳中的溶解度测定与相关

构造了用于固体溶质溶解度测量的半流式装置，以研究甲基水杨酸（MSA）异构体在超临界二氧化碳（ScCO ₂）中的溶解度。测量水杨酸在ScCO _2中的溶解度，以试图验证设备和实验程序的可靠性。在9-18.5 MPa的压力范围内，分别测量了三种MSA异构体3-MSA，4-MSA和5-MSA的溶解度，分别为308.2 K，318.2 K和328.2K。结果表明，MSA异构体的溶解度在8.3×10 ^–6到5.9×10 ^–4的范围内。这些新测得的溶解度数据通过四个半经验模型进行了关联。获得了令人满意的相关结果，溶解度的平均绝对相对偏差在8.17％之内。与Chrastil和Méndez-Santiago和Teja模型的良好相关性结果证实了溶解度数据的一致性。