Prospects for SCR denitrification catalysts: With the current level of pollutant emissions, NOx emissions will reach 30 million t by 2020. the current rapid growth of NOx emissions in China has exacerbated the deterioration of regional acid rain, even partially offsetting the huge efforts made in SO2 control in China [4]. Statistics show that the growth of NOx emissions in China has led to a shift in acid rain pollution from sulphuric acid to a combination of sulphuric and nitric acid, with the proportion of nitrate ions in acid rain rising gradually from 10% in the 1980s to 30% in recent years. NOx is also an important cause of regional fine particle pollution and haze, and due to the significant increase in NOx emissions in recent years, atmospheric visibility in China is decreasing and hazy weather is increasing. Therefore, NOx emission control has become an important task for air pollution control.

2MnOx/Al2O3 denitrification catalyst

As an amphoteric oxide with high thermal stability, Al2O3 is also an excellent low-temperature SCR carrier because it has abundant acidic sites and can better adsorb the reactants NO and NH3, which is conducive to the catalytic reaction. Wen Qingbo [29] prepared a denitrification and denitrification catalyst Fe0.05Mn0.09Ce0.05Ox/γ-Al2O3 with the complex oxides formed by three transition metal elements Fe and MnCe as the active components and γ-Al2O3 as the carrier, which has excellent denitrification performance at low temperature, good anti-SO2 performance and long service life. conversion up to 89% and over 98% when the temperature exceeded 170°C, and had good SO2 resistance and long service life. Guo Jing et al[30] used sol-gel method to produce CeO2-MnOx/Al2O3 composite denitrification catalyst, which had the highest catalytic activity at 250°C and denitrification rate of more than 95%. Jin et al[31] loaded Mn and Ce on TiO2 and Al2O3 carriers and evaluated the activity of the two denitrification catalysts. The results showed that the Mn-Ce/TiO2 denitration catalysts were more active from 80 to 150 °C, while the Mn-Ce/Al2O3 denitration catalysts had better catalytic activity above 150 °C.