Levulinic acid is usually obtained from a complex aqueous mixture from which it has to be separated and purified. In this work, the liquid extraction of this acid from water using ionic liquids (ILs) is studied, and the effect of the cationic structure of the ILs is analyzed and discussed from experimental and computational data. For that, liquid-liquid equilibrium data were experimentally determined for {water + levulinic acid + ionic liquid} ternary mixtures. Specifically, the studied extraction agents were NTf₂-based ILs with imidazolium, pyridinium, and sulfonium cations. This work is based on the tie-lines determination through the concentration of the equilibrium phases, which were obtained by density measurements. From these data, the ability of the ILs as solvents was evaluated in terms of selectivity and solute distribution ratio. The obtained results show that high values of S and moderated values of β are achieved, which indicates that these ionic solvents could be considered as a potential alternative to extract this acid from aqueous mixtures. Aiming to gain an improved understanding of the effect of the cation on the phase behavior of these systems, a theoretical study was also carried out with the quantum chemical COSMO –RS. This tool has quite satisfactorily applied to find an explanation of the phase equilibria in terms of molecular interactions between the involved compounds.

通常从复杂的水性混合物中获得白蛋白酸，必须将其分离和纯化。在这项工作中，研究了使用离子液体（ILs）从水中液体萃取这种酸的方法，并从实验和计算数据中分析和讨论了ILs阳离子结构的影响。为此，通过实验确定{水+乙酰丙酸+离子液体}三元混合物的液-液平衡数据。具体而言，研究的萃取剂为NTf ₂咪唑，吡啶鎓和sulf阳离子的基于IL的离子液体。这项工作基于通过密度测量获得的平衡相浓度确定的联系线。根据这些数据，根据选择性和溶质分布比评估了ILs作为溶剂的能力。获得的结果表明，较高的S值和中等的β值结果表明，这些离子溶剂可被视为从水性混合物中提取该酸的潜在替代品。为了更好地了解阳离子对这些系统的相行为的影响，还使用量子化学COSMO –RS进行了理论研究。该工具已经非常令人满意地应用于根据所涉及化合物之间的分子相互作用来寻找相平衡的解释。