Abstract Cosolvents are employed to improve the extraction efficiency and modify the selectivity of the main solvent. However, choosing a proper cosolvent in supercritical extraction is an arduous task. This study aimed to predict the best cosolvents for the supercritical CO2 extraction of oleic and linoleic acids using the Hansen solubility theory. Calculations were performed for eight organic cosolvents used in food and pharmaceutical production. The best cosolvents for the solubilization of both fatty acids were short-chain alcohols, ethanol and methanol. The predictions were validated with bubble pressures of the mixtures with a 0.003 fatty acid molar fraction at temperatures of 313.2 K and 323.2 K. The experimental results agreed with the predictions. The effect of pressure was well predicted via the direct relationship between pressure and the solvent density. However, the impact of temperature was not properly foreseen because the variation of solute vapour pressure was not considered. The Hansen theory predicted that the miscibility enhancement of the solute in the supercritical mixture is maximum at low pressures and low cosolvent concentrations, as was experimentally confirmed.

中文翻译：

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使用汉森溶解度理论预测在超临界 CO 2 中溶解脂肪酸的最佳助溶剂

摘要 助溶剂用于提高萃取效率和改变主溶剂的选择性。然而，在超临界萃取中选择合适的助溶剂是一项艰巨的任务。本研究旨在使用 Hansen 溶解度理论预测用于油酸和亚油酸超临界 CO2 萃取的最佳助溶剂。对食品和药品生产中使用的八种有机助溶剂进行了计算。溶解两种脂肪酸的最佳助溶剂是短链醇、乙醇和甲醇。在 313.2 K 和 323.2 K 的温度下，使用脂肪酸摩尔分数为 0.003 的混合物的气泡压力验证了预测。实验结果与预测一致。通过压力和溶剂密度之间的直接关系可以很好地预测压力的影响。然而，由于没有考虑溶质蒸气压的变化，因此没有正确预见温度的影响。Hansen 理论预测，超临界混合物中溶质的混溶性增强在低压和低共溶剂浓度下最大，正如实验所证实的那样。