Bismuth effect on the Co-Mn/Ce0.85Zr0.15O2 nanoparticulate for CO preferential oxidation in simulated syngas

► Adding Bi notably improves catalytic properties of the supported Co-Mn catalysts. ► The effect of Bi is significantly affected by the Bi adding method and loadings. ► There exists obvious synergism between Bi and the Co-Mn/Ce0.85Zr0.15O2 catalyst. ► 100% CO removal occurs at 175-225 °C over Bi-modified catalyst in simulated syngas. ► The developed novel Co-based catalyst can be a promising candidate for CO PROX.