Catalytic preferential oxidation of carbon monoxide over platinum supported on lanthanum ferrite–ceria catalysts for cleaning of hydrogen

Abstract

Since hydrogen is produced by reforming of hydrocarbon it contains carbon monoxide (CO). In order to make hydrogen suitable for proton exchange membrane fuel cell application there is need to reduce concentration of CO less than 100 ppm. Water–Gas-Shift reactions subsequent to reforming lower CO concentration in H2 to about 1–1.5% by volume. Preferential oxidation of CO (PROX–CO) using a catalyst is therefore important for further cleaning up of CO from H2. The catalyst in this study is platinum supported over lanthanum ferrite–ceria (Pt/LaFeO3–CeO2) exhibits excellent activity of 99.8% and selectivity of 95.7% at a relatively lower temperature of 100 °C with an equivalence ratio of 3 for PROX–CO. The concentration of CO is reduced from 1% v/v in feed to ca. 30 ppm in product gas with relatively lower loss of hydrogen is the most significant achievement in this study. The catalyst is selective towards CO oxidation as the hydrogen loss is relatively low (ca. 3.8%) and there is no methane formation. The improvement in catalytic activity and selectivity is attributed to the strong metal support interaction and open morphology of catalyst. The results obtained in this study reveal the excellent catalytic activity by using LaFeO3–CeO2 as support for Pt catalyst.