Solubility of Fish Oil Components in Supercritical CO2 and CO2 + Ethanol Mixtures

Abstract

Solubility measurements for squalene, vitamin A palmitate, orange roughy oil, spiny dogfish liver oil, and commercial cod liver oil in supercritical carbon dioxide are reported over the temperature range 313−333 K and pressure range 200−300 bar. Solubility measurements are also reported for squalene, orange roughy oil, spiny dogfish liver oil, and cod liver oil in supercritical carbon dioxide + ethanol mixtures over the pressure range 200−300 bar at 333 K, and ethanol mass concentrations up to 12% by mass on a solute free basis. The use of ethanol as an entrainer substantially increased the solubility of all fish oil components. The increase in solubility, S, with ethanol concentration at fixed temperature and pressure was correlated by the empirical equation S = S0 exp(kX), where S0 is the solubility in pure CO2 at given temperature and pressure, k is a fitted constant, and X is the mass fraction of ethanol on a solute-free basis.