Enhanced Resistance to Pb Poisoning of the Co‐modified Mn/Fe‐pillared Clay Catalysts for NH3‐SCR at Low Temperatures

Abstract Lead (Pb) is a heavy metal commonly found in industrial exhaust gases, which can reduce catalytic activity of a catalyst for the NH 3 ‐SCR reaction. In this study, 4.0 wt% Mn‐loaded Fe‐pillared interlayer clay (4Mn/Fe‐PILC) and its Co‐modified catalyst (2Co‐4Mn/Fe‐PILC) were prepared, in the meanwhile the 4Mn/Fe‐PILC‐Pb and 2Co‐4Mn/Fe‐PILC‐Pb samples were also obtained using the impregnation method with a Pb(CH 3 COO) 2 aqueous solution. It was found that the addition of 2.0 wt% cobalt could significantly enhance Pb resistance of the 4Mn/Fe‐PILC catalyst. The characterization results revealed that the doping of Co to Mn/Fe‐PILC increased the surface Mn 4+ species concentration, reducibility, and acid site amount, thereby improving Pb resistance of the catalyst. Furthermore, the in situ DRIFTS results demonstrated that Co modification enhanced the adsorption capacity of NH 3 or NO, especially influenced formation of the NH 3 intermediates and bridging nitrate species, which were also conducive to the improvement in Pb resistance of the catalyst.