Insight into the promotion mechanism of activated carbon on the monolithic honeycomb red mud catalyst for selective catalytic reduction of NO_(x)  

作　　者：Qiuzhun Chen Xiang Zhang Bing Li Shengli Niu Gaiju Zhao Dong Wang Yue Peng Junhua Li Chunmei Lu John Crittenden 

机构地区：[1]National Engineering Laboratory for Coal-Burning Pollutants Emission Reduction,School of Energy and Power Engineering,Shandong University,Jinan,250061,China [2]Brook Byers Institute for Sustainable Systems and School of Civil and Environmental Engineering,Georgia Institute of Technology,828 West Peachtree Street,Atlanta,GA,30332,USA [3]State Key Joint Laboratory of Environment Simulation and Pollution Control,National Engineering Laboratory for Multi Flue Gas Pollution Control Technology and Equipment,School of Environment,Tsinghua University,Beijing,100084,China [4]Energy Institute,Qilu University of Technology(Shandong Academy of Sciences),Jinan,250013,China

出　　处：《Frontiers of Environmental Science & Engineering》2021年第5期177-186,共10页环境科学与工程前沿（英文）

基　　金：the National Natural Science Foundation of China(Grant No.21906090);the National Key Research and Development Program(Nos.2017YFC0210200 and 2017YFC0212800);Primary Research&Development Project of Shandong Province(Nos.2018GSF117034 and 2019JZZY020305).

摘　　要：Our previous study proved that the acid-pretreatment process could efficiently activate red mud(RM)for the selective catalytic reduction(SCR)of NO_(x).However,in terms of the molding process,which is the key step determining whether it can be applied in large-scale industrial,the surface acidity and reducibility of catalyst always decreased dramatically,and part of surface area and pore structure were lost.In this study,we prepared monolithic honeycomb red mud(MHRM)catalysts with activated carbon(AC)as an accelerant and investigated the effect of AC on the MHRM.The results showed that the MHRM with 3 wt.%of AC(MHRM-AC3)exhibited the best SCR performance,and kept more than 80%NO_(x)conversion in the range of 325℃–400℃.Compared with the MHRM,MHRM-AC1,and HMRM-AC5,the MHRM-AC3 has more mesoporous and macroporous structures,which can provide more adsorption active sites.The AC significantly improved NH3 adsorption and surface reducibility,which was mainly due to the increase of the surface acid sites(especially the Brönsted acid sites),the concentration of Fe(II),and the surface adsorbed oxygen.The presence of more Fe(Ⅱ)enriched the surface oxygen vacancies,as well as the surface adsorbed oxygen,due to the charge imbalance and unsaturated chemical bond.And surface adsorbed oxygen exhibited more active than lattice oxygen owing to its higher mobility,which was conducive to NO_(x)reduction in the SCR reaction.

关 键 词：Selective catalytic reduction Iron-based catalyst Red mud Monolithic catalyst Activated carbon 

分 类 号：X703[环境科学与工程—环境工程]