Boosting the Performance of Pt-Based Honeycomb Monolithic Catalysts for CO Preferential Oxidation in Hydrogen-Rich Streams via the Channel Rotation

Abstract

CO preferential oxidation (CO-PROX) in H2-rich streams has garnered considerable attention because of the emerging hydrogen economy, including advanced fuel cell technology. Particularly, mass transfer and diffusion at low CO concentrations (1 vol %) are critical factors influencing CO-PROX performance of structured catalyst. In this study, Pt/Fe3O4 catalysts were uniformly coated on honeycomb ceramics, and the stacked arrangement of rotating channels with varying angles (0°, 15°, 30°, and 45°) was proposed to enhance CO diffusion in channels. By employing computational fluid dynamics (CFD), the velocity, CO mole fraction, and pressure were systematically analyzed, and the underlying angle–performance relationship was then elucidated. Through this cost-effective rotation strategy, flow perturbations were induced as gas transitions between monoliths, which prompted a shift from laminar to turbulent flow and altered velocity and reactant distribution. At a rotation angle of 45°, the CO conversion was boosted by 5–13%. This work underscores the pivotal role of our innovative catalyst design in revolutionizing the CO-PROX reactions to pave the way for enhanced efficiency and practical implementation in various industrial applications.