As metabolic intermediates, volatile fatty acids (VFAs) can be recovered by separation and purification and contribute to the economy. It was necessary, however, to investigate the optimization of liquid–liquid extraction (LLE) in this study because of the technical difficulties encountered during the recovery of VFAs. For this reason, the organic solvents diethyl ether, trioctylamine, and toluene were investigated as LLE solvents to extract VFAs from Baker’s yeast industry effluent, which contains high levels of organic matter. An optimal pH value of 3 was determined by a pH scan performed between pH 2.5 and pH 7.5. Principal component analysis (PCA) was used to determine the effects of organic solvents and pH on extraction efficiency. The extraction efficiency was evaluated using the optimal pH and multi-stage extraction experiments. In a three-stage extraction, diethyl ether recovered 82% of the VFAs, making it a promising organic solvent for extracting VFAs from anaerobic fermentation broth. PCA revealed that an opposite correlation between VFA recovery and pH for each organic solvent. Based on the results of the cost analysis, it was determined that the costs of recovering VFAs were reduced by 90% per kilogram.

中文翻译：

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液液萃取从面包酵母工业废水厌氧发酵液中回收挥发性脂肪酸


作为代谢中间体，挥发性脂肪酸（VFA）可以通过分离和纯化来回收，并有助于经济。然而，由于 VFA 回收过程中遇到的技术困难，有必要在本研究中研究液液萃取 (LLE) 的优化。因此，研究人员研究了有机溶剂乙醚、三辛胺和甲苯作为 LLE 溶剂，从有机物含量较高的面包酵母工业废水中提取 VFA。通过在 pH 2.5 和 pH 7.5 之间进行 pH 扫描确定最佳 pH 值为 3。主成分分析 (PCA) 用于确定有机溶剂和 pH 对萃取效率的影响。使用最佳pH值和多级提取实验评估提取效率。在三阶段萃取中，乙醚回收了 82% 的 VFA，使其成为从厌氧发酵液中提取 VFA 的有前途的有机溶剂。 PCA 显示每种有机溶剂的 VFA 回收率和 pH 值之间存在相反的相关性。根据成本分析结果，确定回收VFA的成本每公斤可降低90%。