THE SOLUBILITY OF 2 MONOTERPENES IN SUPERCRITICAL CARBON-DIOXIDE

The solubilities in supercritical CO2 of two terpenes, alpha-pinene as a representative of the monoterpene hydrocarbons and cis-verbenol as one of the oxygenated terpenes, have been measured at temperatures fro m 40 to 55-degrees-C and pressures from 5 to 12 MPa using a dynamic fl ow apparatus, which was tested by measuring the solubilities of naphth alene in compressed carbon dioxide. The experimental solubility data w ere correlated using a compressed gas model with the Peng Robinson equ ation of state and empirical equations based on the dependence of the concentration of solute on the density of pure solvent. The unknown cr itical properties of both monoterpenes were estimated using the Joback contribution method. The vapour pressure of cis-verbenol was determin ed by the modified Watson method. The optimum conditions for the super critical fluid extraction of both monoterpenes were determined.