Solubilities and adsorption equilibria of β-carotene in supercritical and near-critical fluids

Abstract

A systematic investigation of solubility and adsorption equilibria of β-carotene in carbon dioxide and propane, respectively, at elevated pressures was carried out. Investigated at (303, 313, and 323) K and over a pressure range from (3.2 to 13.4) MPa, the solubility of β-carotene in propane was in the range of (110 to 450) mg·kg-1 propane and approximately 2 orders of magnitude higher than that in supercritical carbon dioxide. Adsorption equilibria of β-carotene in carbon dioxide with a modifier and in propane were studied on nonpolar chromatographic adsorbents. Concerning adsorption equilibria of β-carotene in carbon dioxide with 2-propanol as a modifier, the loading decreases with increasing modifier content and increasing pressure. Regarding the adsorption equilibrium of β-carotene in propane, the loading achieved is much lower than in carbon dioxide due to the higher solubility of β-carotene in propane.