Ce?Mn-doped Modification Copper-based Catalysts For Selective Catalytic Reduction Of Nitrogen Oxides

Along with the fast speed development of economy,science and technology,the demand of fossil around people's life is very high.When fossil fuel is burning will produce a larde amount of NOx,which will pollute the environment and make human?s health weakly.Selective catalytic reduction,especially ammonia as a reducing agent,is used to treat nitrogen oxides as harmless nitrogen and water.The most ideal processing technology,the key to implementing this technology is to design a highly efficient and durable heterogeneous catalyst.The widely used catalyst is V₂O₅-WO₃?MoO₃?/TiO₂,V₂O₅ is biologically toxic,and the catalyst has a narrow reaction temperature range and limited water and sulfur resistance.In view of these shortcomings,the design and development of low-toxic,non-toxic,nitrogen oxides Denitration catalysts with high removal efficiency,excellent sulfur and water resistance,and economical and durable have important application value.In response to this demand,this paper proposes a new system of a new type of Cu-based catalysts in which Ce and Mn are etched into the surface of Cu₂O by redox displacement reaction and then subjected to high temperature treatment to obtain a composite of highly dispersed Ce and Mn elements.For the selective reduction of nitrogen oxides by ammonia.OES-ICP,XRD,TEM,SEM,XPS,H₂-TPR,NH₃-TPD and other characterization methods were used to analyze the composition,structure and surface composition of the catalyst group,and the catalyst was dehydrated by the laboratory.The denitrification performance of sulfur and water and sulfur poisons was systematically investigated and compared.The mechanism of catalytic denitration of catalysts was also explored by in-situ infrared spectroscopy.The specific research and results are as follows:?1?Firstly,the characterization and performance research of Cu-based denitration catalysts were established by embedding Ce red oxide on Cu₂O surface.By modifying the amount of Ce embedded,a binary metal oxide surface composite catalyst with optimized composition,uniform dispersion of Ce and tightly compounded on the surface of Cu substrate was obtained.Compared with the conventional sample prepared by deposition precipitation method,the surface of Ce was embedded.It can significantly improve the distribution of Cu?I?species on the surface and improve the redox performance of the catalytic interface.It can be close to practical conditions in the reaction space velocity of 100000 h^-1,SO₂ exists,and the reaction temperature range of 280?-320?.The conversion of NO is 90%and the N₂ selectivity is 95%.?2?Based on the above work,further introduction of Mn,Ce and Mn are embedded in the surface of Cu₂O to obtain a ternary copper-based catalyst with a highly dispersed Ce\Mn\Cu composite oxide surface.The results show that Ce and Mn are obtained.Co-embedding,even after high temperature treatment,the Cu species on the catalyst surface maintains the distribution of Cu?I?species as the main component,compared to the conventional catalysts and binary catalysts with Cu?II?species as the main surface composition.The wider temperature range shows better water and sulfur resistance and efficient removal of NO,and the catalytic cycle performance is stable.