Low-temperature SCR of NO with NH 3 over noble metal promoted Fe-ZSM-5 catalysts

We have reported previously the excellent performance of Fe-exchanged ZSM-5 for selective catalytic reduction (SCR) of NO with ammonia at high temperatures (300–400 °C). In this work, we found that the reaction temperature could be decreased to 200–300 °C when a small amount of noble metal (Pt, Rh, or Pd) was added to the Fe-ZSM-5. The SCR activity follows the order Pt/Fe-ZSM-5 > Rh/Fe-ZSM-5 > Pd/Fe-ZSM-5 at 250 °C. On the Pt promoted Fe-ZSM-5, 90% NO conversion was obtained at 250 °C at GHSV  = 1.1 ×  10 5  h −1 . Moreover, the noble metal improved the resistance to H 2 O and SO 2 . The presence of H 2 O and SO 2 decreased the SCR performance only very slightly.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44250/1/10562_2004_Article_3462.pd