Kinetic study for the extraction of succinic acid with TOA in fermentation broth; effects of pH, salt and contaminated acid

• Published in: Biochemical engineering journal Vol. 36; no. 1; pp. 8 - 13
• Main Authors: Jun, Young-Si, Lee, Eun Zoo, Huh, Yun Suk, Hong, Yeon Ki, Hong, Won Hi, Lee, Sang Yup
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 15.08.2007; Amsterdam Elsevier Science; New York, NY
• Subjects: Biological and medical sciences; Biotechnology; Diffusion-reaction; Extraction kinetics; Fermentation; Fundamental and applied biological sciences. Psychology; Liquid–liquid extraction; Microporous membrane; Salts; Stirred cell; Succinic acid; Tri- n-octylamine; Microporous membrane; Salts; Diffusion-reaction; Succinic acid; Stirred cell; Liquid–liquid extraction; Tri- n-octylamine; Fermentation; Extraction kinetics; Salinity; Liquid-liquid extraction; pH; Membrane; Extraction; Kinetics; Tri-n-octylamine
• ISSN: 1369-703X; 1873-295X
• DOI: 10.1016/j.bej.2006.06.011

Reactive extraction can be used for the recovery of carboxylic acids from fermentation broth. Through the formation of complex with extractants at the two-phase interface, the carboxylic acids are partitioned into organic solvents. However, the recovery of carboxylic acids is interrupted by the conditions of fermentation broth. In this study, the effects of conditions of fermentation broth on the extraction kinetics were investigated using a microporous membrane-based stirred cell for the extraction of succinic acid with tri- n-octylamine. The interfacial concentrations of species in various systems were correlated and thus the effects of pH, salts and contaminated acid on the intrinsic reaction kinetics were discovered. The reaction rate constants were determined from the forward reaction rate equation reported in our previous work. It was found that the extraction rates were steeply decreased at pH values larger than 3 due to the dissociation of carboxylic group. Competitive extraction of salts, which were HPO 4 2− (or PO 4 3−), CO 3 2− and SO 4 2−, and contaminated acid, which was pyruvic acid, had negative influence on the extraction process of succinic acid and thus the extraction rates were decreased. The interfacial concentrations of succinic acid and TOA in fermentation broth had no difference with those in artificial single acid systems. Therefore, the decrease of extraction rates can be explained by the change of ionic strength in fermentation broth.