Abstract：
Olive oil production leads to the generation of olive mill wastewater (OMWW). Due to the presence of phenolic compounds, they are difficult to process, but they represent a source of high-added value chemicals since they have antioxidant and therapeutic properties. This work has studied the extraction of phenolic compounds from a type of OMWW, olive vegetation water, which presents these compounds in a more diluted dosage than in other studied to date, to revalue this waste stream. A real olive vegetation water from a Spanish olive oil producer was used, and liquid-liquid extraction was applied. Terpenoids and terpene-based hydrophobic eutectic solvents were systematically used to extract phenolic compounds following the concentrations of tyrosol, catechol, caffeic acid, and total phenolic content. By molecular simulation with the COSMO-RS method, 4 terpenoids, and 2 eutectic solvents were selected and compared with 2 conventional solvents. The Solvent/Feed ratio in the extraction of phenolic compounds was studied, showing that the solvents with the highest extraction results were geraniol, eucalyptol, and eutectic solvent menthol + camphor, which outperformed conventional solvents methyl isobutyl ketone and diisopropyl ether. Menthol + camphor gave total phenol extraction yields of 88.73% at a Solvent/Feed ratio in volume of 0.50, surpassing all solvents tested. A solvent reuse and regeneration process was applied by back-extraction of the 4 solvents: FTIR results showed the stability of the solvents while maintaining yields in the solvent reuse process. The phenolic compounds could be concentrated in the alkaline phase to factors up to 49.3 to the initial concentration in olive vegetation water. The alkaline phases were neutralized to obtain a precipitate with a caffeic acid content of up to 26 % wt%, and a tyrosol-rich supernatant with a concentration of up to 6.54 g/L. This work proposes a process using natural solvents to extract phenolic compounds from olive vegetation water.
摘要：
橄榄油生产导致橄榄厂废水(OMWW)的产生。由于酚类化合物的存在，它们很难处理，但它们代表了高附加值化学品的来源，因为它们具有抗氧化和治疗特性。这项工作研究了从OMWW中提取酚类化合物，橄榄植被水，与迄今为止的其他研究相比，这些化合物的剂量更加稀释，重新评估这条废物流。使用了来自西班牙橄榄油生产商的真正的橄榄植被水，并采用液-液萃取法。萜类化合物和萜类疏水低共熔溶剂被系统地用于提取酚类化合物，儿茶酚,咖啡酸,和总酚含量。通过COSMO-RS方法的分子模拟，4萜类化合物，选择了2种共晶溶剂，并与2种常规溶剂进行了比较。研究了萃取酚类化合物的溶剂/进料比，表明提取结果最高的溶剂是香叶醇，桉树脑,和低共熔溶剂薄荷醇+樟脑，其性能优于常规溶剂甲基异丁基酮和二异丙基醚。薄荷醇+樟脑在溶剂/进料体积比为0.50时得到88.73%的总苯酚提取率,超过所有测试的溶剂。通过4种溶剂的反萃取来应用溶剂再利用和再生过程:FTIR结果显示溶剂的稳定性,同时保持溶剂再利用过程中的产率。酚类化合物可以在碱性相中浓缩至橄榄植被水中初始浓度的49.3倍。中和碱性相以获得咖啡酸含量高达26％wt％的沉淀物，和浓度高达6.54g/L的富含酪醇的上清液。这项工作提出了一种使用天然溶剂从橄榄植被水中提取酚类化合物的方法。
