Vitamin E acetate (VEA) exhibits promising pharmacological action in the pharmaceutical and cosmetic industries. The solubility of VEA in supercritical carbon dioxide is measured to determine the cloud-point pressures in a highpressure variable-volume view cell at various temperatures (i.e., 308.15, 313.15, 318.15, 323.15, and 328.15 K) and pressures (8−15 MPa). The experimental results indicate that the solubility of VEA can be improved by increasing pressure and reducing temperature in the experimental range. Furthermore, four density-based semiempirical models are employed to correlate and predict the experimental results, including Chrastil, Kumar and Johnston (K-J), Bartle, and Mendez-Santiago and Teja (MST) equations. The theoretical calculation results are consistent with the determinatal results.

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Vitamin E acetate (VEA) has been widely used as medicines, nutrients, and cosmetic additives. Solubility data are generally used to aid the design of processes to prepare products that provide the required dosage of the active compound(s). In this study, the static cloud-point method is employed to determine the solubility of VEA in supercritical carbon dioxide (scCO 2 ) with ethanol (0.5, 1.0, and 2.0 mol %) as the cosolvent at temperatures of 313.15, 318.15, 323.15, and 328.15 K, and pressures of 8−15 MPa. The results show that the solubility of VEA in scCO 2 can be remarkably enhanced by adding ethanol as the cosolvent. It could also be increased with the enhancing pressure and the decreasing temperature at the constant ethanol concentration. Furthermore, some semiempirical models including Christil-G, K-J, Bartle, MST-S, Reddy, and Peŕez are employed to correlate the experimental data. The average absolute relative deviations values of these models range from 2.43 to 6.86%, indicating that these models could well predict the VEA solubility data in scCO 2 + ethanol systems of this study.

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In this study, Camellia oil is co‐extracted from Camellia oleifera seeds and green tea scraps by supercritical carbon dioxide (SC‐CO2), which is optimized on the extraction yield, ABTS‐scavenging activity, and total polyphenols content (TPC) of oil by single‐factor experiments combined with response surface methodology (RSM). The extraction temperature, pressure, dynamic time, carbon dioxide (CO2) flow rate, and seed mass ratio were investigated with single‐factor experiments. The results indicated the optimum CO2 flow rate and dynamic extraction time were 15 L hour−1 and 60 min (i.e., 2.382 kg CO2/100 g sample). Furthermore, the complicated effects of extraction temperature (40–50 °C), pressure (20–30 MPa), and seed mass ratio (0.25–0.75) were optimized by RSM based on the Box–Behnken design (BBD). The models with high R‐squared values were obtained and used to predict the optimum operating conditions of the process. Under the optimum operating conditions (i.e., temperature of 46 °C, pressure of 30 MPa, and seed mass ratio of 0.35), the extraction yield, ABTS‐scavenging activity, and TPC of oil were 14.43 ± 0.17 g/100 g sample, 73.70 ± 0.34%, and 2.18 ± 0.05 mg GAE/g oil, which were in good agreement with the predicted values. In addition, the experiments indicated that the Camellia oil obtained was rich in polyphenols, resulting in better oxidation stability and antioxidant activity than the original oil.