Abstract

SCR (Selective Catalytic Reduction)-type Lean NOx catalyst ,which have continuously good activity of NOx reduction under the condition of excess oxygen, was focused for the NOx reduction in lean-burn exhaust gas.In this study, the advancement of NOx conversion can be achieved by using Ir (iridium) catalyst. And the NOx selectivity, which in competitive HC oxidizing reaction, is improved by using new catalyst support.Furthermore, the catalyst durability is improved by coating the material, which can convert NO to NO2, with the catalyst. The improved catalyst have good performance for practical use.The improvement Ir catalyst showed the highest conversion in reduction of NOx (63%) on Japanese 10-15 mode, under the lean condition, with the engine controlling according to catalytic properties.

References

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Author (organization or company)

• Ken OGAWA（Tochigi R&D Center）
• Kazuhide TERADA（Tochigi R&D Center）
• Tomomi SUGIYAMA（Tochigi R&D Center）
• Takeshi NARISHIGE（Tochigi R&D Center）
• Isao KOMORIYA（Tochigi R&D Center）

Publication Information

Article of Honda R&D Technical Review Vol.12 No.2 (99 - 104)

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Citation Information