Research Status and Progress of Catalysts for High-Temperature NH₃-SCR Reaction

Nitrogen oxides (NOx) are key pollutants in the atmospheric environment, contributing to acid rain, photochemical smog, and ozone depletion while posing serious threats to human respiratory health. Ammonia selective catalytic reduction (NH3-SCR) technology has emerged as a mainstream method for NOx removal due to its high denitrification efficiency. However, NH3-SCR catalysts suffer from poor thermal stability, low N2 selectivity, susceptibility to hydrothermal deactivation, and chemical poisoning under high-temperature conditions (> 400 °C), severely hindering their practical application and widespread adoption in high-temperature operational environments. This paper systematically reviews research progress on high-temperature NH3-SCR catalysts, providing detailed discussions categorized by catalyst type: metal oxide catalysts (V-based, Ce-based, and Fe-based), zeolite catalysts (CHA structure, Beta structure, and MOR structure), and other types (MOF-derived catalysts, monolithic catalysts). It thoroughly analyzes the deactivation mechanisms of various catalysts under high-temperature conditions and summarizes corresponding mitigation strategies. Finally, it identifies current research bottlenecks and outlines future research directions, aiming to provide theoretical support and technical references for the practical engineering application of NH3-SCR high-temperature catalysts.