Supercritical Antisolvent Precipitation Combined with UV Spectroscopy for Measuring Solubility in CO2–Solvent Mixtures

We have proposed a new method for measuring solubility in multicomponent fluids, which relies on supercritical antisolvent precipitation in combination with UV spectroscopy (SAS–UVS). Using acetylsalicylic acid as an example, we have compared solubility measurement results obtained by the method proposed in this study to literature data. On the whole, the acetylsalicylic acid solubility data obtained by the SAS–UVS method agree with literature data: the values are on the same order independent of conditions. In the vast majority of our experiments, the solubility values obtained by the SAS–UVS method fall between those obtained by a dynamic method and SAS–SFC (supercritical fluid chromatography). These results provide indirect evidence for adequacy of our data.