摘要：

BACKGROUND Bioconversion is a promising route to produce bio-based building blocks such as 3-hydroxypropionic acid (3-HP). Reactive extraction can be used for 3-HP recovery, and ultimately integrated to the bioconversion process. To the best of our knowledge, there is no published experimental data about the reactive extraction of 3-HP. This work aimed to study the extraction of 3-HP using tri- n -octylamine and Aliquat 336 as extractants in n -decanol. Comparison was also made with its positional isomer, lactic acid. Finally, the extraction of 3-HP from model and real bioconversion broths was examined. RESULTS The use of mixed extractants showed high performances over a wide range of experimental conditions, highlighting a synergistic effect. A possible extraction mechanism considers the formation of a ternary complex between TOA, Aliquat 336 and the carboxylic acid. When 3-HP was extracted from a real bioconversion broth, some cell-originating compounds were suspected to adsorb to the aqueous–organic interface. This effect, added to the possible competition between 3-HP and compounds that can react with the extractants, led to limitations in the yield ( Y %) and selectivity (α 3HP ) of the extraction. For example, Y % and α 3HP were respectively 89% and 35.9 for the model bioconversion broth and decreased to 62% and 15.7 for the real broth at pH = 3.2. CONCLUSION Effective experimental conditions for the reactive extraction of 3-HP were pointed out for the first time. Further work will be undertaken with a view to better elucidating the mechanisms involved in real conditions of an integrated extractive bioconversion system. 2015 Society of Chemical Industry

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