Efficient Concentration of an Amino Acid Using Reactive Extraction Coupled with Bipolar Electrodialysis

Abstract

One intention of the PRODIAS (processing diluted aqueous systems) project is to develop and establish a toolbox of innovative and tailored separation technologies applicable to design energy-efficient water removal and product recovery techniques. Within this project, the recovery of γ-aminobutyric acid (GABA) was investigated. Using both synthetic as well as fermented solutions, reactive extraction of GABA with the solvent di-(2-ethylhexyl)phosphoric acid + isododecane was performed. For back extraction, different mineral acids were examined. Multistage countercurrent reactive extraction using pH adjustments along the stages to increase extraction efficiency as well as back extraction were then run on pilot-plant scale with fermented GABA solutions. The resulting GABA salt from back extraction was finally split by means of bipolar electrodialysis.