本研究建立一套半流動式裝置用於量測不同溫度（308.2 K、318.2 K、328.2 K）及壓力（90 ~ 185 bar）條件下甲基水楊酸異構物於超臨界二氧化碳中之溶解度數據，研究之固體溶質為：水楊酸、3-甲基水楊酸、4-甲基水楊酸。其中水楊酸在308.2K下之溶解度量測實驗目的在於驗證實驗設備與手法的可行性，並以相同實驗設備及手法量測3-甲基水楊酸與4-甲基水楊酸之溶解度實驗數據。在取得溶解度實驗數據後，利用由結合律為基礎的半經驗式模型—Chrastil model、由稀釋溶液理論出發推演的Mendez-Santiago and Teja model以及多參數模型進行回歸計算，皆能得到良好回歸結果。本研究亦使用Chrastil model與Mendez-Santiago and Teja model進行數據自身一致性測試，以確認實驗數據具一致性。;In this study, the solid solubility of the isomers of methylsalicylic acid in supercritical carbon dioxide was measured using a semi-flow type apparatus at different temperature (308.2 K、318.2 K、328.2 K) over the pressure range from 90 to 185 bar. The solid solutes studied in this work were salicylic acid, 3-methylsalicylic acid, and 4-methylsalicylic acid. The solubility of salicylic acid in supercritical carbon dioxide at 308.2 K was measured to validate the reliability of the apparatus and experimental procedures. The result of salicylic acid shows a well satisfactory agreement with experimental data reported in literature. Using the same apparatus and experimental procedures, the solubility of 3-methylsalicylic acid and 4-methylsalicylic acid were successfully obtained and correlated by three semi-empirical models, Chrastil model, Mendez Santiago and Teja model (MST model), and multi-parameter model. The consistency of solubility data was confirmed by the good correlation results obtained with Chrastil model and MST model.