Jr. Gonzalezvelasco et al., INFLUENCE OF WATER AND HYDROCARBON PROCESSED IN FEEDSTREAM ON THE 3-WAY BEHAVIOR OF PLATINUM-ALUMINA CATALYSTS, Applied catalysis. B, Environmental, 12(1), 1997, pp. 61-79
The influence of water and the nature of the hydrocarbon -methane, eth
ylene, propene and 1-butene- processed in the feedstream on the three-
way behaviour of a ceria-modified alumina supported platinum catalyst
is investigated. Experiments were carried out with static feedstreams
with air-to-fuel ratios between 14.13 and 15.17 as well as with oxidiz
ing-reducing cycled feedstreams simulating the real automobile exhaust
mixture. Conclusions are drawn on the importance of water-gas shift a
nd steam reforming reactions and their relationship with inhibition se
lf-poisoning effects of carbon monoxide and/or hydrocarbons. Compariso
n of data of the prepared catalyst and those obtained at the same oper
ational conditions with two commercial catalysts, with only platinum/a
lumina and platinum-rhodium/ceria-alumina respectively, allows confirm
ation of the effects of ceria and establishes the role of rhodium when
added to the catalyst.