The Differential Recycle Reactor for Efficient Kinetic Measurements in Heterogeneously Catalyzed Gas-Liquid Reactions

Obtaining reliable kinetic data for heterogeneously catalyzed gas-liquid reactions underindustrially relevant conditions is difficult because conventional laboratory reactors oftenprovide limited control over hydrodynamics and yield little kinetic information perexperiment. This work presents a differential recycle reactor (DRR) for rapid kineticmeasurements in gas-liquid fixed-bed catalysis. The reactor enables controlled gas andliquid flow through the catalyst bed, operation at elevated temperatures and pressures,and time-resolved kinetic data from a single batch experiment. Two reactor designs weredeveloped and evaluated based on bed structure, fluid distribution, and suitability for kineticanalysis. Model-based sensitivity studies identified operating windows in which theDRR approaches ideal batch-reactor behavior, enabling accurate kinetic evaluation witha simplified batch model. The predicted behavior was validated experimentally throughan industrially relevant core hydrogenation. The results show that the DRR is a practicalmethod for efficient macrokinetic measurements under realistic operating conditions andis suitable for routine kinetic studies and future coupling with online analytics.