Catalytic denitration activity and sulfur resistance of modified siderite catalysts

The siderite denitration catalysts modified by Ce and Zr were prepared by mixing and stirring method. The effects of Ce and Zr co-doping on the catalytic denitration performance and sulfur resistance of the catalyst were studied. The results show that the 3%Ce+3%Zr-doped siderite catalyst(Ce_0.03/Zr_0.03-siderite) has the highest catalytic denitration activity and good sulfur resistance. The catalytic denitration efficiency is above 92% in the temperature range of 180-330 ℃. Furthermore, the denitration efficiency is still more than 95% after introducing SO₂ gas with a volume fraction of 0.01% for 8 h at 210 ℃. The characteristics of the catalyst, such as components, microporous structure and crystal phase were determined by XRF, BET, XRD, NH₃-TPD, TG and other experimental means. The characterization results show that the doping of Ce and Zr can significantly improve the specific surface area and surface crystal dispersion of the catalyst, enhance the surface acidity of the catalyst, and promote the decomposition of ammonium sulfate on the catalyst surface; thus the modified siderite catalyst has an excellent low-temperature catalytic denitration activity and a good sulfur resistance.