Preparation of double-modified MIL-53 and its catalytic de-nitration performance

Four kinds of MOFs materials were prepared by microwave hydrothermal method, which were applied to simulate low-temperature SCR technology to treat high-concentration NOx, and MIL-53 materials were screened out. It is subjected to double modification of ligand modification and element (such as Zr) doping modification. The results show that the MIL-53 material doped with 10% Zr element after amino modification, when the reaction temperature is 200℃, the initial concentration of flue gas is 800-1900mg/m³, and the ratio of ammonia to nitrogen is 1:1. The denitration efficiency is relatively stable at 75%-85%, which is 40% higher than that of the unmodified material. The removal efficiency of NO₂ can reach up to 90%. The characterization results show that the doping modification can increase the number of coordination bonds, increase the proportion of chemically adsorbed oxygen, enhance the redox ability, and improve the adsorption and catalysis. Compared with traditional materials, it has better resistance to CO₂ interference and continuous use.