| Summary: | 碩士 === 國立成功大學 === 化學工程研究所 === 82 === Perovskite-type catalysts are able to catalyze both reduc- tion
and oxidation that make it possible to be treated as three- way
catalysts. To simulate the poisoning environment of three- way
catalytic converter in the automobile engine for the poison-
ing of the perovskite, we used a Pulse-Flame reactor to proceed
the lead and phosphorus poisoning of the catalysts. The activi-
ties of catalysts before and after poisoned were monitored by
the oxidation of toluene. After poisoning, the catalysts La0.3
Sr0.7CoO3 and SrCoO3 showed large increment in their activities
while others showed little increment or even decrement on their
activities. When using ICP to analyze the amount of lead
adsorb- ed on the surface of catalysts, we found that the
amount of lead adsorbed on the surface of manganate-based
catalysts were pro- portional to the amount of Sr substitution
and the specific sur- face area of catalysts. However, cobalt-
based catalysts did not follow these rules. The amount of
cobalt with the valence state of +3 in the catalysts became
larger after poisoning when ana- lyzed with SIMS. We also
investigated the surface component of La0.3Sr0.7CoO3 with ESCA,
we found that the O 1s spectra of this poisoned catalyst has a
high energy BE shifting to 535 +- 0.5eV. This might be due to
the carbonate ion bound in the catalysts. (the following is
omitted)
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