Abstract To achieve efficient low‐temperature denitrification, a series of Ce‐Cr‐Fe/AC catalysts and alkali‐metal‐poisoned catalysts were prepared by an impregnation method using activated carbon as the support. The effects of different alkali metal (K or Na) loadings and Ce concentrations on the alkali resistance of the catalysts were systematically investigated. When the K or Na loading reached 1%, the catalytic activity decreased by more than 20% within the temperature range of 120–240°C. The introduction of Ce effectively alleviated the deactivation caused by alkali metal poisoning. To elucidate the mechanisms underlying the effects of alkali poisoning and Ce modification on NO x conversion, the Ce‐1K/Fresh and Ce‐1Na/Fresh (Fresh = 8Fe6Cr/AC) catalysts were characterized by X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area analysis, H 2 temperature‐programmed reduction (H 2 ‐TPR), NH 3 temperature‐programmed desorption (NH 3 ‐TPD), X‐ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). The results revealed that the addition of K or Na decreased the number of surface acid sites, reducibility, surface area, and the contents of Fe 3+ , Cr 3+ , and surface active oxygen (O β ). However, Ce doping effectively suppressed these adverse effects. Furthermore, the 8Ce/Fresh catalyst exhibited excellent resistance to H 2 O and SO 2 during a 400 min stability test, demonstrating its superior durability and potential for practical applications under complex flue gas conditions.
Liu et al. (2026) studied this question.