Preparation And Denitration Activity Of Manganese Base Composite Pillared Clay Catalyst

With the speeding up of industrialization and modernization in our country,China's nitrogen oxide emissions remain high.And it has created serious environmental problems such as acid rain,photochemical smog.Selective catalytic reduction(SCR)is a mature technology relative to other denitration technology,Because of high NOx removal efficiency and low rate of ammonia escape,it has become the mainstream of denitration technology.The vanadium catalyst has been widely applied in coal-fired power plant,but vanadium catalyst is easy poisoned by high cost and high denitration temperature faults.Based on cheap easy montmorillonite as the carrier,through the different elements column tide preparation column montmorillonite carrier,active component for Mn,through traditional impregnation method for low temperature SCR denitration catalyst.Through index NOx conversion and N2 selectivity of catalysts,evaluate the denitration catalyst activity at low temperature.The catalyst preparation parameters,the different elements of column tide and different composite element column proportion for denitration catalyst activity,XRD,N2-adsorption,scanning electron microscopy,energy spectrum analysis and NH3-TPD.The influence on the activity of catalyst denitration was studied by the three preparation parameters:calcining temperature,Mn load and catalyst calcining temperature by using MnOx-Zr-PILM as the object.Research shows that the optimal parameters for Zr column brace montmorillonite catalyst of preparation temperature is 400?,Mn load of 10 wt.%and catalyst calcination temperature is 300?.The denitration active experimental results shows that As the reaction temperature rises,NOx conversion rises and the N2 selectivity decreased.According to optimizing the preparation parameters.The effect of single columnar solation catalyst on denitration activity was studied in Al,Cr and Fe.Researches shows that the physical and chemical properties of the catalyst were affected by different column support vectors.The pore diameter structure and specific surface area of the catalyst for the mono-element column of the manganese-based single element were studied through N2 adsorption desorption isotherm.The surface area of montmorillonite is larger than the previous.The pore diameter is mainly mesoporous fracture type pore.Specific surface area from big to small for MnOx-Fe-PILM>MnOx-Cr-PILM>MnOx-Al-PILM.The dispersion of the active component manganese in the catalyst surface was studied by SEM and XRD.It is found that 10wt.%manganese has good dispersion.The order of single element column brace montmorillonite preparation of low temperature SCR denitration catalyst:MnOx-Fe-PILM>MnOx-Cr-PILM>MnOx-Al-PILM.The two elements of Cr and Fe are combined with Zr elements and the catalyst for SCR denitration of manganese base composite column was prepared.The influence of the proportion of the composite column on the activity of the SCR catalyst was studied.Research shows that:the MnOx-Zr5Cr15-PILM catalyst has the most optimal NOx conversion rate in the entire temperature range.The efficiency of the catalyst with pure Zr was equivalent in the whole temperature range.The active MnOx-Zr5Fe15-PILM catalysts have optimal NOx conversion of the different ratio column of the Zr and Fe.It is higher than that of manganese base iron column brace montmorillonite catalyst.The catalyst for different proportions of Zr-Fe has the better N2 selectivity in the whole experimental temperature range.The addition of Fe elements can reduce the oxidation of the catalyst,inhibit the generation of N2O,and improve the N2 selectivity of the catalyst.