Progress of performance optimization for Mn-based SCR catalysts at low temperature

The emission of nitrogen oxides (NOx), the primary air pollutant in China, reached 8.96 million tons in 2022, considerably higher than the emissions of volatile organic compounds, particulate matter, and sulfur dioxide (SO2). NOx emission control is the focus and challenge with respect to air pollution management in China. Selective catalytic reduction (SCR) is widely employed to control the emission of NOx in industrial flue gas because of its high efficiency and stability, and it can be used to realize ultralow NOx emission. A catalyst is a vital factor of the SCR technology. Commercial V2O5/TiO2 catalysts have satisfactory tolerance to poisoning factors such as SO2 and H2O, and the operating temperature is generally in the high-temperature range of 300–420 ℃. Although the catalysts can be more effectively adapted to the medium-temperature range of 200–300 ℃ by increasing the loading amount of V2O5, their low-temperature activity is poor at temperatures less than 200 ℃. The development of efficient and stab