Supercritical carbon-dioxide extraction of terpenes from cold-pressed Valencia orange oil

Terpene hydrocarbons in citrus peel oils are unstable and degrade to undesirable compounds due to the action of heat, light and oxygen. The feasibility of using a supercritical carbon dioxide extraction process and pilot scale system to remove terpenes from cold-pressed Valencia orange oil was studied. Design modifications of the commercial pilot system was necessary to achieve the application intended in this study. These modifications consisted of removing 30 mL of tubing, incorporating a preheater and sampling valves, including a new separator unit with a cooling facility, replacing the CO;Pressure and temperature were optimized to obtain the best separation of terpenes which resulted in concentration of oxygenated flavor compounds. Solubility of orange oil in supercritical carbon dioxide was studied within the temperature and pressure ranges of 40-70;Conditions that gave the highest amount of extract were 40;A group contribution equation of state was used to describe the system from a thermodynamical point of view. Predictions of the model were not satisfactory at temperatures close to the critical point. Fugacity and activity coefficients of limonene and linalool were calculated for the vapor and liquid phases, respectively.;As a result of this work, the suitability of supercritical CO...