459234 Optimal Operation of Batch Enantiomer Crystallization: From Ternary Diagrams to Predictive Control
In this work, we investigate the operation and control of a batch crystallization process for a racemic compound forming system with a fines trap and dissolution tank, and seeding of the initial liquid within the system (which is enriched in the desired enantiomer) with crystals of the desired enantiomer. We use the ternary diagram in the development of operating conditions for the system and for the development of constraints for an optimal control design for the system. We develop model equations for the batch crystallization process based on a population balance model for the crystals coupled with mass balances. We then apply a model predictive control strategy to the system to maximize the volume of crystals developed from the seeds while reducing the volume of crystals developed from nucleation, and show how the closed-loop trajectories are related to the ternary diagram thermodynamic data.
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