Modification of liquid film thickness by the action of centrifugal force in a falling film microreactor: Effect on the overall process performance of a catalytic cyclohexene hydrogenation

Abstract

This work presents a process intensification strategy for mass transfer enhancement by developing a system that provides centrifugal acceleration to a falling film microreactor (FFMR). The effective interfacial area for mass transfer was increased by modifying the liquid film at varying flow rates due to the applied centrifugal force's influence. The Nusselt and Kapitza correlations often utilized in predicting liquid film thickness were modified to account for an externally induced force acting normal to the flow direction. Consequently, the effect on film thickness was quantified, enabling the assessment of the overall process performance at different rotational speeds of the reactor unit.For this purpose, hydrogenation of cyclohexene conducted over a Pt/Al2O3 catalyst coated on the micro channel's surface was used as a model reaction. Overall process performance was significantly improved, and mass transfer rate was enhanced by a factor of more than 4.