Study on the Soot Oxidation Activity and Sulfur Poisoning Resistance of LaCuCeZrO_2‐δ Soot Oxidation Catalyst

ABSTRACT Herein, the fresh and SO 2 ‐processed LaCuCeZrO 2‐δ non‐noble metal oxide composite catalysts prepared by SHS combustion method of SHS were compared and studied, whose catalytic activity and sulfur resistance of the catalysts were analyzed. The catalysts were characterized by XPD, XPS, and other methods, and the improvement effect of La doping on the sulfur resistance of CuCeZrO 2‐δ catalyst was discussed. The conclusion shows that La doping decreases the low‐temperature oxidation activity of the catalyst, and the CO 2 selectivity of the catalyst decreases with the increase of La doping proportion, which may be that the oxidation ability of La is weaker than that of Cu and there is no synergistic effect between La and Ce. However, after La partially replaces the Cu element in CuCeZrO 2‐δ catalyst, the sulfur resistance of the catalyst is significantly improved. The presence of La inhibits the formation of CuSO 3 and retains a certain CuO site for the catalyst. Besides, La itself will also serve as the active site for NO oxidation and will not be affected by SO 2 , so that the more abundant nitrate and nitrite species can ensure the smooth progress of NO oxidation and NO 2 adsorption, greatly reducing SO 2 inhibition on the catalyst.