Abstract

Reduction of the precious metal loading of a catalyst generally causes a decline in light-off performance.Study of the low temperature reaction mechanism of catalysts indicated the importance of the top layer in the reaction, thus increasing reactivity in the top layer was established as an objective. The concentration of precious metals in the top layer was increased, and the thickness of the layers was reduced. At the same time, the preciousmetal loading of the subjacent layer, which contributes little to light-off performance, was reduced by 80%. However, increasing the concentration of precious metals in the top layer caused a reduction in performance due to a sintering effect between the metals. Research was therefore conducted on the employment of a high-thermostability support material (alumina) to control the sintering.This research has enabled the development of a three-way catalyst with significantly reduced precious metal loading while retaining conversion performance equivalent to that of conventional catalysts.

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Author (organization or company)

• Syouji INOSE（Tochigi R&D Center）
• Tatsuya OKAYAMA（Tochigi R&D Center）

Publication Information

Article of Honda R&D Technical Review Vol.17 No.2 (129 - 135)

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