The effect of racemization by exchanging the fluid phase allows the specific manipulation of concentration profiles and seems to be a suitable lever for process intensification on the apparatus level. Similar manipulation of the concentration profiles during the crystallization process can be also realized on molecular level if the racemization is achieved by an enzymatic reaction in which an excess of the counter-enantiomer in the liquid phase is transformed to the preferred one [8, 9]. By coupling crystallization (for conglomerate sys-tems) and racemization (for conversion of the unwanted enantiomer) expected theoretical yield of a pure enantiomer can lead up to 100%. Our goal is to develop a comprehensive study for each operating unit and their subsequent integration in a hybrid process. As a model component for the investigation, the amino acid asparagine in water has been chosen.
The first configuration will be usually applied if there is a need for both enantiomers in pure form (with yields up to 50% for each enantiomer), whereas the second configuration provides just one enantiomer with very high yield (up to 100%). These different configurations for productivity enhancement with regard to preferential crystallization will be presented in this contribution.
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