Influence of TiO2 on Noble Metal Based Catalysts for Lean NOx Reduction with CO

The performance of various noble metal based catalysts for the NOx reduction in the CO-rich conditions of simulated post Euro-IV diesel emissions at low temperature was investigated in this paper. Pd loaded catalyst showed higher catalytic activity than Ir or Rh loaded catalysts. Titania, as one of the support material, clearly promoted the deNOx process due to the synergy with alumina and Palladium. The TiO2 loading was optimized subsequently. As a result, Pd/TiO2/Al2O3 catalyst with Pd loading of 2.0 wt.% and TiO2 loading of 10 wt.% showed the NOx conversions of 25~46% in the temperature range of 200~250°C.