The Effects of Coexistent Compounds on CO Preferential Oxidation in Reformed Gas over a Ru Catalyst

Abstract

The effects of coexistent compounds, such as H₂O and CO₂, contained in hydrocarbon reformed gas on CO preferential oxidation over a Ru catalyst were investigated for residential polymer electrolyte fuel cell (PEFC) systems using the natural gas steam reforming process. The presence of either or both H₂O and CO₂ decreased the CO preferential oxidation removal performance of the Ru catalyst over all temperature ranges. Consequently, the temperature window of the catalyst for reducing CO to less than 10 ppm was narrowed by those compounds.