Fe对MnO_x催化剂低温SCR脱硝性能的影响  

Influence of Fe Modification on MnO_x Catalysts for Selective Catalytic Reduction of NO_x at Low Temperature

作　　者：张信莉[1] 路春美[1] 王栋[1] 徐丽婷[1] 彭建升[1] 

机构地区：[1]山东大学能源与动力工程学院,山东济南250061

出　　处：《锅炉技术》2014年第6期67-71,共5页Boiler Technology

基　　金：国家自然科学基金项目(51276101);教育部博士点基金项目(20120131110022)

摘　　要：采用共沉淀法制备一系列Fe改性的MnOx催化剂,在固定床模拟燃煤烟气气氛下考察其脱硝活性,同时借助N2吸附及XRD等研究Fe添加对MnOx催化剂低温SCR脱硝活性的促进机理。结果表明,Fe的添加显著提高了MnOx的低温NOx转化率,并将其活性温度窗口向低温段拓宽了55℃;其中,Fe0.3Mn0.7Ox催化剂在30 000h-1下具有最佳低温SCR活性,自90℃其NOx转化率均高于95%;铁、锰组分间的协同作用能提高催化剂中锰氧化物的分散度,增大催化剂的比表面积和比孔容并优化其孔径分布,进而提高MnOx催化剂的低温SCR脱硝活性。A series of Fe-modified MnOxcatalysts were prepared by a co-precipitation method and their catalytic activities were tested in a fixed-bed reactor under the simulant flue gas atmosphere.The mechanism of Fe promoting the catalytic performance of MnOxcatalysts for low-temperature selective catalytic reduction（SCR）of NOxwith NH3 was investigated by using N2 adsorption and X-ray diffraction.It was found that with the addition of Fe,NOx conversion of MnOxcatalysts in the low temperature window was dramatically improved and the activity temperature window was widend with its lower limit decreasing by 55℃.Among the tested catalysts,Fe0.3Mn0.7Oxcatalysts exhibited the best low-temperature SCR activity,and NOxconversion was above 95% at 90 ℃ and 30 000h^-1.The synergism of manganese and iron species improved the dispersion of the manganese oxide,optimized the pore size distribution of MnOxcatalysts,and increased its BET surface area and pore volume,which favored the low-temperature SCR reaction over MnOxcatalysts.

关 键 词：Fe改性 MNOX 低温SCR 催化剂 

分 类 号：TK16[动力工程及工程热物理—热能工程]