Impact of Microchannel Reactor Design on Ethanol Synthesis via CO₂ Hydrogenation: A CFD Approach

Computational fluid dynamics (CFD) was used to investigate the impact of reactor geometry on ethanol synthesis via carbon dioxide hydrogenation in a microchannel reactor with integrated cooling channel. CFD modelling was used to construct and test various reactor geometries of varying channel height, channel length, and solid wall thickness to evaluate the potential benefits of microchannel reactors for carbon dioxide hydrogenation processes. Modifications to reactor geometry produced notable improvements in CO 2 conversion. Reducing the channel height and extending the channel length led to a 7.72% increase for a change of 3×10 -4 m in channel height and an 8.14% increase for a 0.10 m change in channel length. Moreover, alterations in solid wall thickness exhibited minimal impact on CO 2 conversion but demonstrated a more pronounced effect on heat transfer efficiency between channels. This enhancement in heat transfer would be advantageous in dissipating the heat generated by the exothermic hydrogenation process. These findings suggest that the development of reactor geometry could improve the efficiency of CO 2 hydrogenation to EtOH.