Dynamic experiments in flow accelerate reaction network definition in a complex hydrogenation using catalytic static mixers

Abstract

Kinetic screening, when conducted in batch or under steady state flow conditions, is time consuming. In this work we leverage transient flow experiments to investigate the hydrogenation of an aryl ketone in a gas–liquid flow reactor, catalyzed by catalytic static mixers and monitored using process analytical technologies. Ramping reactor parameters over time allowed the exploration of different residence times and temperatures in a single experiment, allowing rapid definition of the reaction network. Data analysis using a batch approximation approach and a plug flow reactor approach allowed parameterization of predictive reaction models. A Pd/Al₂O₃ catalyst performed ketone reduction, followed by dehydration to the ethylbenzene derivative. Conversely, Pt/Al₂O₃ and Ru/Al₂O₃ showed aromatic ring hydrogenation as the main reaction pathway, following ketone reduction. The developed workflow is likely to be highly applicable to other chemical systems and reaction types.