(214d) Integration of Enzymatic Reactions into Continuous Countercurrent Extraction Processes with Mixed Surfactant Solutions
In this work, the feasibility of the continuous extractive biocatalysis with cloud-point extraction using mixed surfactant solutions is demonstrated for the first time. Thereby an enzymatic reaction (one step out of penicillin production) was integrated into a continuous extraction process. Since the reaction product was continuously removed, higher yields in comparison to batch experiments were reached. The flexibility of the mixed surfactant systems allows to tune the extraction systems to get the highest separation efficiency. Therefore basic studies regarding the phase behavior, phase separation kinetics and temperature-dependency of the mixed surfactant systems in regards of the continuous (reactive) extraction processes were performed. Further, the interaction between the surfactant and the enzyme in the reactive separation unit were studied.
The general applicability of the heterogeneous enzymatic catalysts in extraction columns, thus preventing the enzyme loss (a disadvantage of the homogeneous enzymatic catalysis) was demonstrated in this work. Thereby different concepts of integration of a heterogeneous biocatalysis in the extraction processes with surfactant-based systems and in continuous extraction columns in general were suggested. The concept of continuous heterogeneous extractive bioactalysis was extended to different types of columns and internals, whereas the usage of structured packings coated with the enzyme-containing gels seemed to be the most promising. Here the key influences of physical and structural properties in mixed surfactant systems were investigated. Additionally, the integration of micellar extraction with the whole cell biocatalysis was examined, using microalgae as a model system.
Summarizing, in this work the potential of the integration of biocatalytic reactions with enzymatic catalysis as well as whole cell biotransformations into continuous extraction with mixed surfactant solutions is revealed.