The influence of the promotion of N-modified activated carbon with iron on NO removal by NH3-SCR (Selective catalytic reduction)

New catalysts based on activated carbon, which may be used for tail-end SCR (Selective catalytic reduction), were studied. They were modified by pre-oxidation, introduction of N-surface groups via impregnation with an aqueous solution of urea and subsequent impregnation with Fe(NO3)3 or Mn(NO3)2. The catalysts modified with Fe and Mn showed similar NO conversion, but the former was characterized by better selectivity and stability. The H2O presence in the SCR mixture led to the decrease of NO conversion at low and medium temperature region, which was totally reversible after the removal of water. However, water positively influenced selectivity.