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

CO\npreferential oxidation (CO-PROX) in H<sub>2</sub>-rich streams\nhas garnered considerable attention because of the emerging hydrogen\neconomy, including advanced fuel cell technology. Particularly, mass\ntransfer and diffusion at low CO concentrations (1 vol %) are critical\nfactors influencing CO-PROX performance of structured catalyst. In\nthis study, Pt/Fe<sub>3</sub>O<sub>4</sub> catalysts were uniformly\ncoated on honeycomb ceramics, and the stacked arrangement of rotating\nchannels with varying angles (0°, 15°, 30°, and 45°)\nwas proposed to enhance CO diffusion in channels. By employing computational\nfluid dynamics (CFD), the velocity, CO mole fraction, and pressure\nwere systematically analyzed, and the underlying angle–performance\nrelationship was then elucidated. Through this cost-effective rotation\nstrategy, flow perturbations were induced as gas transitions between\nmonoliths, which prompted a shift from laminar to turbulent flow and\naltered velocity and reactant distribution. At a rotation angle of\n45°, the CO conversion was boosted by 5–13%. This work\nunderscores the pivotal role of our innovative catalyst design in\nrevolutionizing the CO-PROX reactions to pave the way for enhanced\nefficiency and practical implementation in various industrial applications.