Some unit operations, such as reactors, are easily miniaturised and incorporated into high throughput equipment such as robotic platforms. However, there are currently no units that can replicate stage-wise unit operations such as distillation or reactive distillation on a small scale. Reactive distillation combines chemical synthesis with separation by distillation, but this leads to a non-trivial system; the hardware selection, the components present in the system, the mode of operation and the operating conditions all affect the performance that can be achieved. An important issue in the design of reactive distillation systems is the identification of new catalysts that perform well under reactive distillation conditions
1. Catalysts are crucial in increasing reaction rate when the operating temperature range is limited by the evaporation processes taking place. The main goal of this research is to develop a method, utilizing high throughput technology, which can be used to assess potential catalysts for batch or semi-batch reactive distillation systems.
Key to achieving this target will be the ability to identify whether a candidate catalyst could be suitable as early as possible, ideally using information available from knowledge of the catalyst structure. The approach of this research is to correlate catalyst descriptors/properties to performance in a reactive distillation unit. The case study used is batch and semi-batch reactive distillation for the esterification of long-chain fatty acids. Potential catalysts are experimentally studied at small scale in a high throughput Chemspeed SLT 106 synthesizer. The Chemspeed unit cannot replicate distillation, so a dynamic reactive distillation simulation is employed, built in BatchCAD TM software. Further investigation is performed in a pilot scale batch reactive distillation unit, providing experimental information about the catalyst performance and validation of the strategy.
1. Malone, M. F. and Doherty, M. F. (2000) Reactive Distillation, Ind. Eng. Chem. Res., 39, 3953-3957