Study on visible light catalytic denitrification performance of Ag2O/TiO2 catalyst
WANG Shu-qin1,2, DONG Jian-xin1, LI Jin-meng1
1. Department of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, China; 2. Hebei Key Laboratory of Power Plant Flue Gas Multi-Pollutants Control, North China Electric Power University, Baoding 071003, China
Abstract：Anatase TiO2 was prepared by hydrothermal method and compounded with Ag2O to construct a catalyst. BET, XRD, XPS and other catalysts were used to characterize and analyze the catalysts, and NO was used as the treatment object to explore the influence of reaction conditions on the denitrification efficiency of the catalysts. The results showed that under visible light, when the NO concentration in the reaction system was 23.6mg/m3 and the molar ratio of ammonia to nitrogen was 1:1, the best denitrification efficiency of Ag2O/TiO2 (10%) was 92.00%. Further exploration found that the denitrification efficiency remained basically unchanged by changing the flue gas humidity in the reaction system. And when CO2, SO2, NO and other gases are present at the same time, the denitrification efficiency can be maintained at 71.43%. The characterization results showed that the specific surface area increased, the band gap width decreased, the PL peak intensity decreased, and the photocurrent density increased after recombination with Ag2O. After the reaction, the catalyst has a nitro asymmetric stretching vibration peak, so it is speculated that during the reaction process, ·O2-,·OH,·O radicals act as an oxidant to oxidize NO to NO2 and then further oxidize to NO3- to achieve NOx removal. When NH3 and NO2 exist at the same time, the incomplete reaction of NO is further reduced to N2, which promotes the conversion of pollutant gases and further improves the denitrification efficiency.
王淑勤, 董剑鑫, 李金梦. Ag2O/TiO2催化剂可见光催化脱硝性能[J]. 中国环境科学, 2024, 44(10): 5397-5405.
WANG Shu-qin, DONG Jian-xin, LI Jin-meng. Study on visible light catalytic denitrification performance of Ag2O/TiO2 catalyst. CHINA ENVIRONMENTAL SCIENCECE, 2024, 44(10): 5397-5405.
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