Solubility of Δ9-tetrahydrocannabinol in supercritical carbon dioxide: Experiments and modeling

The solubility of Δ9-tetrahydrocannabinol (Δ9-THC) in supercritical carbon dioxide has been determined at 315, 327, 334 and 345 K and in the pressure range from 13.2 to 25.1 MPa using an analytical method with a quasi-flow apparatus. Prior to performing these measurements, the method was validated by measuring anthracene solubilities and comparing these with literature values. The molar solubility for Δ9-THC ranged from 0.20 to 2.95 × 10−4. The data were correlated using the Peng–Robinson equation of state in combination with quadratic mixing rules. Deviations between calculated results and the experimental data ranged from 4.1 to 13.3% absolute average relative deviation (AARD).