Are noble metal-based water-gas shift catalysts practical for automotive fuel processing?

Several Pt-based water-gas shift catalysts were prepared and tested for activity and stability. Under feed conditions typical of a reformer outlet, low activity and rapid first-order deactivation were observed. Virtually identical deactivation rates were found for all Pt/ceria water-gas shift catalysts tested. A strong dependence of the deactivation rate on the presence of hydrogen in the feed suggests that a large hydrogen fraction may lead to the irreversible overreduction of the ceria; this problem is likely to plague all such noble metal-based systems. (C) 2002 Elsevier Science (USA).