Ti/Sn掺杂CeMn基催化剂的低温脱硝活性及抗水性能  

Low-temperature denitrification activity and water tolerance of Ti/Sn doped CeMn-based catalyst

作　　者：钱立新 丁龙 魏进超[2] 杨本涛 张洪亮 龙红明 王宏涛 Lixin QIAN;Long DING;Jinchao WEI;Bentao YANG;Hongliang ZHANG;Hongming LONG;Hongtao WANG(School of Metallurgical Engineering,Anhui University of Technology,Ma'anshan,Anhui 243002,China;MCC Changtian International Engineering Co.,Ltd.,Changsha,Hunan 410205,China;Anhui Province Key Laboratory of Metallurgy Engineering&Resources Recycling,Ma'anshan,Anhui 243002,China)

机构地区：[1]安徽工业大学冶金工程学院,安徽马鞍山243002 [2]中冶长天国际工程有限责任公司,湖南长沙410205 [3]冶金工程与资源综合利用安徽省重点实验室,安徽马鞍山243002

出　　处：《过程工程学报》2022年第12期1691-1701,共11页The Chinese Journal of Process Engineering

基　　金：国家自然科学基金资助项目(编号:52174290,52004001);中冶长天科研开发基础研究基金(编号:2020JCYJ13)。

摘　　要：采用共沉淀法制备了Ti/Sn掺杂的CeMn基复合金属氧化物催化剂,研究了Ti/Sn改性对CeMnO_(x)催化剂的脱硝性能和抗水性能的影响,并通过物化性能表征对催化剂的微观结构、吸附氨状态、氧化还原能力以及表面元素价态进行了分析。结果表明,Ti和Sn元素的引入均可以提升CeMnO_(x)催化剂低温NO_(x)转化活性和抗水性能,并且Ti的提升效果更加显著,在150~250℃,CeMnTiO_(x)脱硝效率接近100%,在200℃、10vol%H_(2)O条件下,脱硝效率维持在95%以上。H_(2)程序升温还原、NH_(3)程序升温脱附及X射线光电子能谱等检测结果表明催化剂表面Ce-O-Ti和Mn-O-Ti结构的形成提升了催化剂的氧化还原性能,增多了催化剂表面弱酸位、中强酸位数量,同时形成了更多的氧空位,从而使催化剂获得了良好的低温NO_(x)转化活性。Sintering flue gas is faced with serious denitrification pressure,traditional vanadium tungsten titanium catalyst can effectively remove nitrogen oxides in industrial flue gas above 280℃,which is 100~150℃ higher than that of sintering flue gas.The purpose of denitrification can be achieved by heating sintering flue gas,but it will undoubtedly cause huge energy consumption,which is inconsistent with the concept of carbon emission reduction proposed by China.Therefore,it is necessary to develop denitrification catalysts with low-temperature activity.At present,the CeMn-based catalyst can achieve efficient denitrification in the sintering flue gas temperature range and has broad application prospects.In this study,the Ti/Sn doped CeMn composite metal oxide catalysts were prepared by a coprecipitation method.The effect of Ti/Sn modification on the denitrification and water resistance of the CeMnO_(x)catalyst was studied.The microstructure,ammonia adsorption state,redox capacity,and surface element valence of CeMnO_(x)catalyst were analyzed by physical and chemical properties characterization.The results showed that both Ti and Sn elements improve the low-temperature NO_(x)conversion activity and water resistance of CeMnO_(x)catalyst,and Ti presented a more significant improvement effect.At 150~250℃,the denitrification efficiency of CeMnTiO_(x)was close to 100%.When the reaction temperature was 200℃and the mixed gas contained 10vol%H_(2)O,the denitrification efficiency of the catalyst remained above 95%.The results of H_(2)temperature programmed reduction,NH_(3)temperature programmed desorption,and X-ray photoelectron spectroscopy showed that the Ce-O-Ti and MnO-Ti structures in the modified catalyst improve the redox performance of the catalyst,increase the number of weak acid sites and medium strong acid sites on the surface of the catalyst,and form more oxygen vacancies,which made the catalyst exhibit better low-temperature activity.

关 键 词：烧结烟气 低温脱硝 CeMn基催化剂 选择性催化还原 抗水 

分 类 号：X757[环境科学与工程—环境工程] TQ426[化学工程]