Abstract: Extraction of propionic acid by chemical complexation was investigated from simulation solution and fermentation broth. Methyl trioctyl-ammonium chloride（MTAC）diluted with octanol was used for the extraction，which had a higher selectivity for propionic acid over other organic acids and was less affected by pH and inorganic anions. The extraction equilibrium could be reached in 15 min when 1.2 mol/L of MTAC was applied with an extraction phase ratio of 3∶1（organic phase to water phase）. This system was believed to be adaptable for the extraction of propionic acid with high concentration. Over four-stage extraction，86.2% of propionic acid could be extracted.

摘要： 利用络合萃取法对模拟溶液和发酵液中的丙酸分离进行研究。络合剂、稀释剂筛选结果表明：选用甲基三辛基氯化胺（MTAC）为络合剂、正辛醇为稀释剂时，萃取受pH值和无机阴离子影响较小，对丙酸具有较高的选择性。以1.2 mol/L的MTAC为萃取有机相，有机相/水相（体积比）为3的条件下，萃取15 min即能达到平衡；该系统适用于较高浓度丙酸发酵液萃取，经4级萃取丙酸萃取率达86.2%。