Florian Buchbender

A Critical Review of the Application of Drop-Population Balances for the Design of Solvent Extraction Columns: I. Concept of Solving Drop-Population Balances and Modelling Breakage and Coalescence

Population-balances are a powerful method to predict the population behavior of drops in chemical-engineering equipment such as solvent extraction columns. In such columns a complex interaction of different phenomena, namely drop sedimentation, mass transfer, drop breakage and coalescence as well as axial dispersion occurs. In this article the concept of drop-population balances is discussed in detail as well as possible solution methods. Also, a critical review of existing models accounting for breakage and coalescence taking place in extraction columns is presented. Future parts of this series will be devoted to modelling mass-transfer and sedimentation as well as on application of single-drop based modelling.

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.