Solubilities of Binary Systems α-Tocopherol + Capsaicin and α-Tocopherol + Palmitic Acid in Supercritical Carbon Dioxide

Solubilities of two binary mixtures (α-tocopherol + capsaicin and α-tocopherol + palmitic acid) in supercritical carbon dioxide (CO2) are reported in this work. Measurements were done in a semiflow apparatus at 308.15 and 328.15 K and in the pressure interval from 10 to 35 MPa. Equimolar mixtures of the solutes were prepared to perform solubility measurements. Each solubility point was replicated at least three times to check for the repeatability. Solubilities of α-tocopherol were higher than those of capsaicin for the ternary system. Meanwhile, for the binary mixtures α-tocopherol + palmitic acid, their solubilities in supercritical CO2 suffered a shift as temperature increased. The solubility of α-tocopherol was higher than that of palmitic acid at 308.15 K, and the vice versa occurred at 328.15 K. Solubilities were modeled by means of the Peng–Robinson equation of state using the van der Waals mixing rules with two adjustable parameters. Additionally, The Kumar and Johnston model was selected for the ...