Effects of TWC’s PGM Loading Amount on the Exhaust-emission Purification Performance and on the PGM Sintering

三元触媒の貴金属担持量が排気ガス浄化性能と凝集度合いに及ぼす影響

In the three-way catalysts (TWCs), the ability to reduce exhaust-gas emissions is insufficient to cope with real driving conditions such as low temperature below 0°C. To improve the activity of TWCs, the authors' study focused on the exhaust-gas purification performance and the sintering characteristics of platinum-group metal (PGM: palladium, rhodium, and platinum) particles aged at 1000°C. From their extensive analysis of mass-production catalysts covering a wide range of PGM loading amount, it was clarified that the catalysts with enlarged PGM particles after severe aging had higher turnover number than fresh catalysts. Moreover, the purification performance was affected significantly by PGM loading amount. Especially, rhodium catalysts having loading amount more than 4.0 g/L showed high catalytic performance.三元触媒では,将来の排気ガス規制強化に伴い貴金属使用量の増加が懸念されている.触媒性能向上のためには,各貴金属の浄化性能と凝集特性の関係を明らかにする必要がある.実排気1000℃耐久後の解析から,Rh の浄化性能はPd,Pt よりも優れ,その要因は反応に関与する貴金属粒子の表面原子数に起因すると考えた.

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  • Accession Number: 01674172
  • Record Type: Publication
  • Source Agency: Japan Science and Technology Agency (JST)
  • Files: TRIS, JSTAGE
  • Created Date: May 15 2018 3:06PM