Background: As the country attaches increasing importance to environmental protection, the emission standards of coking enterprises are becoming increasingly demanding. During the coking process of enterprises, many pollutants that are harmful to health and harmful to the environment are produced, and nitrogen oxides (NOx) is one of them. Coking enterprises are one of the main sources of NOx emissions. In June 2012, the Ministry of Environmental Protection and other departments jointly promulgated the "Emission Standard for Pollutants in the Coking Chemical Industry"(GB16171 -2012), which clearly requires that starting from January 1, 2015, The NOx emission concentration in the flue gas of all coking enterprises must be less than 500mg/m2, and should be less than 150mg/m3 in special limit areas.] Increasingly strict environmental pressure forces coking companies to seriously consider NOx emission control issues.

Introduction to the results: In view of the large changes in the load of coal-fired power station boilers and the wide fluctuation range of flue gas temperatures in various industrial furnaces, we developed a new system that can adapt to 150 ° C.~Efficient flue gas denitrification catalyst in a 300-degree range. (1) Active components that were less affected by surface sulfate were selected, and MoO3 and Nb2O5 were used as promoters to modify the catalyst to improve the low-temperature denitrification activity of the catalyst. (2) The research found the promoting effect of NH3 and H2O on SO2 on the deactivation of the modified catalyst and the cause of the deactivation, and proposed a method for the catalyst to be resistant to water and sulfur.