Mixed micellar systems in continuous countercurrent extraction columns for biocatalytic reactive separations

研究了表面活性剂双水相体系在生物催化剂反应萃取中的应用。目前，基于表面活性剂的双水相体系已广泛应用于金属离子、蛋白质、生物材料、有机化合物和废水中有毒芳烃的提取和纯化。采用连续转盘式接触器，成功地实现了多级连续装置的首次放大。重要的是，在申请人组中实现了水表面活性剂两相体系在搅拌连续逆流萃取塔中的应用。基于表面活性剂的双水相体系为对有机溶剂和高温敏感的生物分子提供了温和的生存条件。因此，它们用于原位产物去除以增加转化对于环境友好型生物催化和生物转化过程特别有趣。此外，有机溶剂的缺乏为大多数生物催化剂创造了一个方便的环境。胶束体系中的生物催化反应已经在批量实验中进行了研究。然而，目前还没有研究过水表面活性剂两相体系的连续反应过程。本项目的主要目的是证明柱内连续多级胶束萃取作为生物催化剂（酶促反应）反应性分离工艺的原理适用性。因此，应确定混合表面活性剂-添加剂体系的组成对连续萃取过程效率的关键影响。建立混合表面活性剂体系对分子溶质和电离溶质的萃取方法，特别要注意生物催化剂对表面活性剂的稳定性和萃取条件。

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.