Maldistribution susceptibility of monolith reactors: Case study of glucose hydrogenation performance

In this work an ultrafast electron beam modality was applied for the first time to characterise the gas-liquid Taylor flow inside each channel of an opaque honeycomb monolith structure (65 cpsi) for u_(G,S)=0.1…0.5 m/s and u_(L,S)=0.2 m/s. Significant spatial and temporal deviations in the phase holdup as well as in the gas bubble and liquid slug lengths were found. In order to evaluate the impact of Taylor flow maldistribution on the reactor performance, the data of more than 125,000 unit cells were used to simulate the reactor productivity in the hydrogenation of glucose. The results verify that a monolith reactor solely designed by using superficial velocities and empirical correlations for gas bubble and liquid slug lengths fails significantly in achieving high product selectivity and the desired conversion. The developed methods are a solid base to design and select proper distributors ensuring the favourable flow configurations for specific chemical processes.