Solubilities and Densities of Capsaicin in Supercritical Carbon Dioxide at Temperatures from 313 to 333 K

Solubilities of capsaicin in supercritical carbon dioxide were measured at 313, 318, 323, 328, and 333 K in the range of (5-20) × 10^-5 (mole fraction of capsaicin). Measurements were performed in an apparatus based on the static-synthetic method. Good agreement was found between the obtained experimental data and those available in the literature, except for at 333 K. Volumetric properties for the carbon dioxide + capsaicin system were also obtained via a vibrating tube densitometer coupled to the measurement cell in the same range of temperatures and at pressures up to 25 MPa. Densities for this system have not been previously reported. The solubilities of capsaicin in carbon dioxide were correlated with the density-based model proposed by Mendez-Santiago and Teja (Fluid Phase Equilib. 1999, 158-160, 501). The results from the correlation show that the reported data are self-consistent.