Isothermal and temperature gradient supercritical fluid extraction and fractionation of squalene from palm fatty acid distillate using compressed carbon dioxide

Currently the extraction of valuable components from oils is of growing interest. Palm fatty acid distillate (PFAD) is a by-product from palm oil refining process which contains valuable minor components. This work investigated the extraction and recovery of squalene using supercritical carbon dioxide (Sc-CO2) as solvent from PFAD. The process has been carried out on a counter-current glass beads packed column with the dimensions of 11.45 mm internal diameter (I.D.) and 1.5 m of effective height. The effect of the experiment conditions on the squalene purity and recovery has been studied. The pressure and temperature were the operating conditions investigated and they varied from 10 to 20 MPa and 313 to 353 K, respectively. Squalene and free fatty acids (FFA) content in the extract increased, and triglycerides content decreased during most of the fractionation runs. Longitudinal thermal gradient profiles along the column was investigated for further recovery of squalene from PFAD, results showed the highest squalene recovery of more than 95% was reached and concentration of squalene was increased from 2 wt% in the feed to 16 wt% in the top product.