Mixed micellar systems in continuous countercurrent extraction columns for biocatalytic reactive separations
This proposal is focused on the application of surfactant based aqueous two-phase systems for the reactive extraction with biocatalyst. Up to now, surfactant based aqueous two-phase systems have been used in various applications such as extraction and purification of metal ions, proteins, biomaterials, organic compounds and toxic aromatics from wastewater. The first scale-up to continuous multistage units was successfully realized by means of a continuous rotating disc contactor. Importantly, the application of aqueous surfactant two-phase systems in a stirred continuous countercurrent extraction column was achieved in the group of the applicant. Surfactant based aqueous two-phase systems systems provide mild conditions for biomolecules which are sensitive to organic solvents and high temperatures. Thus, their use for an in-situ product removal to increase conversion is especially interesting for biocatalytic and biotransformation processes with regard to environmental friendliness. Furthermore, the absence of organic solvents creates a convenient environment for most biocatalysts. A biocatalytic reaction in micellar systems was already studied in batch experiments. However, a continuous reactive process applying aqueous surfactant two-phase systems was not investigated so far. The main goal of this project is to prove the principle applicability of continuous multistage micellar extraction in a column as a reactive separation process for biological catalysts (enzymatic reactions). Thereby the key influences of the composition of mixed surfactant-additive systems on the efficiency of the continuous extraction process should be identified. The extraction of both molecular and ionized solutes with mixed surfactant systems should be established with the special focus on the stability of the biocatalysts towards surfactants and extraction conditions.