Trace Co doping improves NH3-SCR performance and poisoning resistance of Ce-Mn-based catalysts

Abstract

Trace amounts of Co-doped Ce-Mn-based metal oxide catalysts with various applications were synthesized by a simple redox method. When the molar fraction of doped Co was 3 %, the catalyst possessed comparatively high contents of adsorbed oxygen species (Oads), Mn4+, Ce3+, and Co3+, and exhibited promising catalytic performance. C1M3C-3 % had a wide denitrification temperature window, achieving 80 % NO removal at 87–277 °C and 90 % catalytic combustion of toluene at 171 °C (T90% = 171 °C). Furthermore, the catalyst exhibited satisfactory moisture and sulfur resistance activity and can be regenerated by simple calcination (350 °C, 4 h). The reason for the high sulfur resistance of C1M3C-3 % was investigated in detail and a schematic diagram was provided. The NH3-SCR process was revealed to satisfy the L-H mechanism with the assistance of in situ DRIFTS. This work demonstrated that the Co-doped Ce-Mn-based catalyst had the potential for downstream of soot treatment equipment.