Prozessentwicklung für die kontinuierliche dynamisch kinetische Racematspaltung
A dynamic kinetic resolution is an interesting and reasonable extension for a simple kinetic resolution. Especially for the connection of an enzymatic catalysed kinetic resolution and a chemical catalysed racemisation very good results are known from literature. Common compatibility problems between both reactions and interaction between both catalysts require a long development which is a criterion of exclusion for many industrial processes. Within this thesis a reaction engineering solution has been developed that allows a free choice of catalysts, independent of limitations which could arise from a compromise of the reaction conditions. This has been achieved by an areal separation of reactions, i. e. racemisation and kinetic resolution. Since modern chemical reactions tend to be done in a continuous way the process has been developed accordingly. By using supercritical carbon dioxide (scCO2) as a mobile phase in such process the effort for the final down stream processing can be reduced enormously or the down stream processing can be directly integrated. By simulating different process concepts reachable conversion and selectivity could be shown and compared among each other. Suitable catalysts for the racemisation have been identified from literature, examined in regards to their applicability and have been selected for further experiments. To make the process of a continuous dynamic kinetic resolution in combination with scCO2 accessible for different enzymes the development of a biphasic system with water as the reactive phase and CO2 as the non reactive phase has been expedited. For that purpose the ability to measure the pH of the water phase under high pressure and to vary the pH in a controlled manner has been developed. Afterwards the influence of different reaction conditions on the enzyme activity was investigated in that biphasic system. To get the ability to do enzymatic reactions in a continuous way in such a biphasic system, different methods for enzyme immobilisation have been examined. For testing the developed concept of a continuous dynamic kinetic resolution a pilot plant has been designed and built that meet different requirements. Furthermore an applicable online analytic has been established. The experiments of continuous dynamic kinetic resolutions in this pilot plant have shown a successful design of the pant and first promising results.
info:eu-repo/classification/ddc/540, Chiralität <Chemie>, Enzymkatalyse, Reaktionstechnik, Immobilisiertes Enzym, Prozesssimulation, Kohlendioxid, Chemie, Dynamisch kinetische Racematspaltung, überkritischer Kohlenstoffdioxid, Dynamic kinetic resolution, supercritical carbon dioxide
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