Selective catalytic reduction (SCR) is currently the most widely used flue gas denitrification technology,with the core methodSCR denitrification catalyst. The presence of the As element in coal combustion fly ash can cause catalyst poisoning and a significantdecrease in service life,affecting the stable and efficient operation of the SCR system. V-Mo/Ti catalysts with different mass fractions ofMoO3 (3% and 7%) were prepared,in order to improve the As resistance of V-Mo/Ti catalyst. The As poisoned catalysts were alsoprepared by wet impregnation method. The physiochemical properties of the fresh and As-poisoned catalysts were characterized by XRF,ICP, XRD, N2-physisorption, H2-TPR, XPS, NH3-TPD, and O2-TPD. The NOx conversion and N2O concentration of the differentcatalysts in the temperature range 230−410 ℃ were tested via a micro fixed-bed reactor. The results show that As has negative influenceson the pore structure of the catalyst,and reduces the specific surface area,pore volume,reducibility,acidity,and the amount of Oα of thecatalyst. As a result,the catalytic activity of the catalyst declines and the generation of by-product N2O promotes. With the increase ofMoO3 content,the pore structure of catalyst is improved,the decrease in specific surface area and pore volume is reduced,the reductionperformance and surface acid content are increased,and the denitrification activity of catalyst is increased. High mass fraction of MoO3(7%) can reduce the poisoning effect of As on the V-Mo/Ti catalyst. The catalytic performance of V-Mo(7)/Ti-As catalyst is obviously higher than that of the V-Mo(3)/Ti-As catalyst. In the other word,the As resistance of V-Mo(7)/Ti catalyst is superior to that of the V-Mo(3)/Ti catalyst.

岳彦伟(1996—),男,甘肃临洮人,助理工程师。E-mail:yueyw@dteg.com.cn

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YUE Yanwei,HUANG Li,WANG Suqin,et al. Investigation of arsenic resistance of plate-type De-NOx catalyst[J].Clean Coal Technology,2024,30(11):75−81.