Mn/Fe改性碳基催化剂低温脱硝特性  

Low Temperature NO Reduction of Carbon-based Catalysts Modified by Mn/Fe Oxides

作　　者：潘磊 卢平[1] 徐贵玲[1] 陈丹丹[1] 黄震 宋涛 PAN Lei;LU Ping;XU Guiling;CHEN Dandan;HUANG Zhen;SONG Tao(School of Energy&Mechanical Engineering,Nanjing Normal University,Nanjing 210023,Jiangsu Province,China;Jiangsu Jiaxin Environmental Protection Engineering Co.Ltd,Yangzhong 212211,Jiangsu Province,China)

机构地区：[1]南京师范大学能源与机械工程学院,江苏省南京市210023 [2]江苏佳鑫环保工程有限公司,江苏省扬中市212211

出　　处：《中国电机工程学报》2021年第24期8510-8519,共10页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51476079)。

摘　　要：以椰壳活性炭为载体,以硝酸锰和硝酸铁为活性添加组分,采用硝酸氧化、等体积浸渍、中低温煅烧等相结合的方法,制备了Mn-Fe/HAC碳基催化剂。利用固定床脱硝实验台对碳基催化剂脱硝性能进行了评价,并结合傅里叶转换红外光谱(Fourier transform infrared spectroscopy,FT-IR)、N;吸附-脱附、扫描电镜(scanning electron microscopy,SEM)-mapping和X-射线光电子能谱(X-ray photoelectron spectrometry,XPS)等表征结果,探讨了碳基催化剂脱硝及其抗硫抗水机理。结果表明,Mn改性可以显著提升碳基催化剂的脱硝效率,Mn和Fe共同改性在有效提高碳基催化剂脱硝效率的基础上,使得其脱硝窗口温度下移至120℃。Mn-Fe改性催化剂的最佳负载量为7%Mn和0.5%Fe,最佳煅烧为中温400℃氮气煅烧与低温200℃空气煅烧组合煅烧法。Fe添加有效促进了Mn在碳基催化剂表面的均匀分布,并显著提高了Mn;和表面吸附氧(O;)的含量。在6%O;以及无水和SO;条件下,7Mn0.5Fe/HAC催化剂在温度为120℃下的脱硝效率可达82.0%,而在140-240℃脱硝效率则基本稳定在95%。Mn和Fe复合改性碳基催化剂具有良好的抗硫抗水性能,在温度为180℃、含有100μL/L SO;和6%H;O的模拟烟气下,7Mn0.5Fe/HAC催化剂的脱硝效率可达85%以上。Based on the carrier of coconut shell activated carbon and active components of manganese nitrate and ferric nitrate,carbon-based catalyst modified by Mn-Fe oxides was prepared by using a combined methods of nitric acid oxidation,constant volume impregnation,and medium-low temperature calcination.NO reduction of as-prepared carbon-based catalysts was carried out in a fixed-bed reactor.The mechanism of NO reduction and its resistance to SO;and water by carbonbased catalyst was discussed on the basis of measurements of Fourier transform infrared spectroscopy (FT-IR),N;adsorption-desorption,SEM-mapping and XPS.The obtained results indicate that Mn modification can effectively enhance NO reduction efficiency of carbon-based catalyst.And the addition of Fe and Mn not only improves NO reduction of carbon-based catalyst,but also makes window temperature downward to 120℃.The optimum loading capacity of Mn-Fe carbon-based catalyst is 7%Mn and 0.5%Fe,and the combined calcination with nitrogen calcination at 400℃and air calcination at 200℃is an optimal calcination method.The addition of Fe can effectively promote the uniform distribution of Mn on the surface of the carbon-based catalyst,and significantly increase the contents of Mn;and surface adsorbed oxygen (O;).Under the conditions of 6%O;and without water and SO;,NO reduction efficiency of7Mn0.5Fe/HAC catalyst reaches 82.0%at 120℃,and can be stable at 95%at 140-240℃.Mn-Fe carbon-based catalyst has a good resistance performance to SO;and moisture.NOreduction efficiency of 7Mn0.5Fe/HAC catalyst can reach more than 85%under the conditions of temperature of 180℃,100μL/L SO;and 6%moisture in the simulated flue gas.

关 键 词：选择性催化还原 碳基催化剂 低温脱硝 Mn/Fe改性 

分 类 号：TM85[电气工程—高电压与绝缘技术]