Novel Design Integrating a Microwave Applicator into a Crystallizer for Rapid Temperature Cycling. A Direct Nucleation Control Study
| Autor: | Marilena Radoiu, Rohit Kacker, Herman J. M. Kramer |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Work (thermodynamics)
Materials science Particle number 010405 organic chemistry business.industry Nucleation Microwave applicator General Chemistry Temperature cycling 010402 general chemistry Condensed Matter Physics 01 natural sciences Article 0104 chemical sciences law.invention Crystal law General Materials Science Crystallization Saturation (chemistry) Process engineering business |
| Zdroj: | Crystal Growth & Design, 17(7) Crystal Growth & Design |
| ISSN: | 1528-7483 |
| Popis: | The control of nucleation in crystallization processes is a challenging task due to the often lacking knowledge on the process kinetics. Inflexible (predetermined) control strategies fail to grow the nucleated crystals to the desired quality because of the variability in the process conditions, disturbances, and the stochastic nature of crystal nucleation. Previously, the concept of microwave assisted direct nucleation control (DNC) was demonstrated in a laboratory setup to control the crystal size distribution in a batch crystallization process by manipulating the number of particles in the system. Rapid temperature cycling was used to manipulate the super(under)saturation and hence the number of crystals. The rapid heating response achieved with the microwave heating improved the DNC control efficiency, resulting in halving of the batch time. As an extension, this work presents a novel design in which the microwave applicator is integrated in the crystallizer, hence avoiding the external loop though the microwaves oven. DNC implemented in the 4 L unseeded crystallizer, at various count set points, resulted in strong efficiency enhancement of DNC, when compared to the performance with a slow responding system. The demonstrated crystallizer design is a basis for extending the enhanced process control opportunity to other applications. A novel crystallizer design with integrated microwave heating has been demonstrated. Crystal size distribution was manipulated, and different crystal mean sizes were obtained by controlling the nucleation under the direct nucleation control (DNC) framework. Improved efficiency of DNC was achieved with halving of the batch time, for the best case scenario, when compared to use of a slow responding system. |
| Databáze: | OpenAIRE |
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