With USY as the carrier,Fe and Mn composite oxide as the active ingredient,the Mn-Fe/USY catalysts with different proportions of powders were prepared by equal volume impregnation method,it was applied to low temperature SCR denitrification after desulfurization and dust removal.The effects of active component content on catalyst activity and SO 2and H2O toxicity were studied.The specific surface area,solid phase structure,microstructure and functional structure of the catalyst were characterized by specific surface area(BET),X-ray diffraction(XRD),scanning electron microscopy(SEM)and infrared spectros-copy(FTIR).The results showed that 7Nn-Fe/USY had good low temperature denitrification activity. When the reaction temperature is 210℃,when the space velocity is 10 000 h -1and the oxygen content is 5%(volume fraction),the denitrification efficiency reaches 60%;has better resistance to water and sulfur dioxide resistance,but resistance to sulfur dioxide is poor water resistance;at the same time,the effect of H2O on the catalyst is reversible,and SO2irreversibly deactivates the catalyst.The Mn-Fe/USY catalyst has a large specific surface area,and MnOxand FeOxare uniformly dispersed on the carrier USY.The sur-face of the carrier has a large number of Bronsted acid sites and more active intermediates.%以USY为载体,Fe和Mn复合氧化物为活性组分,通过等体积浸渍法制备了不同比例粉末状的Mn-Fe/USY催化剂,应用于脱硫除尘后的低温SCR脱硝.考察了活性组分含量对催化剂活性以及抗SO2和H2O中毒性能的影响.采用比表面积(BET)、X射线衍射(XRD)、扫描电镜(SEM)和红外光谱(FTIR)等手段表征了反应前后催化剂的比表面积、固相结构、微观形貌及官能团结构.结果表明,7Mn-Fe/USY 有较好的低温脱硝活性,在空速为10000h-1,氧气含量为5%(体积分数),反应温度为210℃时,脱硝效率可达到60%;有较好的抗水能力和抗SO2能力,但同时抗水抗SO2能力较差;同时H2O对催化剂的影响是可逆的,SO2对催化剂造成不可逆的失活.各种表征表明,Mn-Fe/USY催化剂有较大的比表面积,MnOx和FeOx呈无定形态均匀分散在载体USY上,载体表面有大量的Bronsted酸位和较多的活性中间产物.
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