Abstract: The poisoning effects of As on traditional SCR catalysts based on V2O5-TiO2 used in a coal fired power plant were studied under the laboratory conditions. The catalysts were characterized by means of H2-TPR，XPS and NH3 adsorption FT-IR. The activity of the catalyst decreased after As poisoning，and the higher the concentration of As，the more significant the decrease of catalytic activity. The chemical forms of W and Ti on the surface were not influenced by As，but V presented various states. Arsenic reduced the number of Bronsted acid on the surface，but did not change the acidity and pathway of catalytic reaction significantly.

Key words: environment, SCR, catalyst, V2O5-WO3/TiO2, arsenic, chemical form, Bronsted acid

摘要： 以某燃煤电厂钒钛基选择性催化还原（SCR）脱硝催化剂为研究对象，在实验室条件下模拟了该催化剂的As中毒，考察了不同浓度的As对催化剂活性的影响，结合H2-TPR、XPS、NH3吸附FT-IR实验分析As对催化剂性能的影响。结果表明催化剂As中毒后，其活性下降，并且As浓度越大，活性下降越明显；催化剂表面的W和Ti的化学形态不受As的影响，而V物种出现多样化；As对催化剂表面的酸性位有一定的影响，使其吸附NH3的Bronsted酸位减少，而对其酸强度和催化反应途径的影响并不显著。

关键词: 环境, 选择性催化还原, 催化剂, V2O5-WO3/TiO2, 砷, 化学形态, B酸