Purification of tocochromanols from edible oil

Extraction of phytosterols and tocopherols from rapeseed oil waste by supercritical CO2 plus co-solvent: A comparison with conventional solvent extraction

In the present study, modified extraction methods using supercritical CO₂ were investigated in order to obtain high-added value compounds from rapeseed oil deodorizer distillate and comparisons were done with modified Soxhlet extraction (solvent extraction + silica). For supercritical fluid extraction (SFE), the optimal extraction parameters were temperature of 40 °C, pressure of 350 bar (for phytosterols), 400 bar (for tocopherol), 5 wt% ethanol as co-solvent, and saponification pretreatment. The optimized SFE procedure led to the recovery of three main phytosterols (50 wt % β-sitosterol, 23.91 wt % Brassicasterol, and 36.25 wt % Campesterol) and only α-tocopherol. Moreover, there was no synergistic effect with saponification pretreatment + co-solvent and the efficiency and concentration of target compounds were less than supercritical CO₂ + co-solvent. Also, comparative Data showed that the efficiency of phytosterols and tocopherols was approximately three times higher (p < 0.05) in SFE relative to modified Soxhlet extraction. Furthermore, the use of ethanol (5 wt %) as co-solvent, improved phytosterols and tocopherol efficiency and purity. The SFE technique offers various advantages over the modified Soxhlet extraction technique, including increasing the solubility of tocopherols and sterols by using CO₂+ co-solvent, minimized usage of toxic organic solvents and increased purity of extracted products.

Extraction of Oil and Minor Compounds from Oil Palm Fruit with Supercritical Carbon Dioxide

A significant quantity of tocochromanols and carotenoids remains in the residual from palm oil production by traditional screw pressing. Supercritical carbon dioxide extraction was used as alternative method with the purpose to recover better these valuable minor compounds. Total oil yield and co-extracted water were investigated in the course of extraction. Tocochromanols and carotenoids were evaluated, not only in the extraction oil, but also in the oil of residual fibre. Modelling of extraction process was also performed for a further up-scaling. The results showed that oil yield up to 90% could be observed within 120 min. Supercritical carbon dioxide (SCCO2) could extract tocochromanols and carotenoids with concentration in the same range of normal commercial processing palm oil, while co-extracted water remained rather low at a level of 2–4%. Moreover, recovery efficiencies of these minor compounds were much higher in case of extraction processed with supercritical carbon dioxide than those with screw pressing method.

Mutual solubility study in supercritical fluid extraction of tocopherols from crude palm oil using CO₂solvent

In this article, the mutual solubility of tocopherols from crude palm oil was studied using carbon dioxide as a solvent at the temperatures of 80, 100 and 120 °C. Each sample from the phase equilibrium unit contained two parts. The liquid part was analyzed by gas chromatography (GC) in order to measure the tocopherol composition and, on the other hand, the vapor phase was conducted in an expansion vessel in order to measure the pressure increment during the expansion process. Two phase equilibrium data was calculated using the liquid phase composition and pressure increments during the expansion process. Results showed that the maximum solubility of tocopherols was around 2.27% at a temperature of 120 °C and at pressure of 5.44 MPa.

Separation processes for organic molecules using SCF Technologies

Supercritical fluids have been applied for many years for the separation of solutes from solids or solute mixtures in both exploratory and industrial applications. In the pharmaceutical industry the generation of pure solid states without impurities is important as the presence of impurities can result in a change in chemical properties or lead to physical instability. The literature on the separation and purification of solutes from solid matrices and solute mixtures using supercritical fluids, with the main emphasis on pharmaceutically important molecules, is reviewed in this article. Also discussed is the application of supercritical fluids in the control of process impurities such as chemical intermediates and residual solvent and in polymorphic control and chiral resolution. As the generation of organic molecules of pharmaceutical interest with high purity is important in pharmaceuticals this review additionally provides a brief overview of highly selective chemical reactions in supercritical fluids.