Preparation Of Ce_xTi_1-xO₂Composite Oxide And The Research Of Desulfurization And Denitrification Performance

S02and NOx in coal-fired flue gas is two of the major air pollutants. Desulfurization and denitrification by means of catalytic reduction is a method of reducing SO2to elemental sulfur and NOX to N2by CO from flue gases. It is a promising method with potential industrial application prospect to purify harmful gases and recycle sulfur resources. Researching and developing excellent catalysts plays vital role in the application of this technology.In this thesis, A series of CexTi1-xO2(x=0-1.0) composite oxide materials are prepared as catalysts by means of coprecipitation. Then we study the relationship between the composition of CexTi1-xO2and structure, and its catalytic performance. And then we focus on the effect of preparation conditions on the activity of catalyst. Finally, we evaluate the desulfurization and denitrification activity of catalyst prepared under optimized conditions. The main research content is as follows:(1) The study of the relationship between the composition of CexTi1-xO2(x=0～1.0) and catalytic performance indicates that:When x decreased from0.5to0.8, the catalytic activity CexTi1-xO2is better. When x=0.7, under the confirmed reaction conditions, the composition of reaction gases0.3%SO2+0.6%CO, the removal rate of SO2is67.2%.(2) The catalytic activity of Ce0.7Ti0.3O2catalysts is improved by optimizing preparation conditions. The appropriate technological conditions are:pH value is10, the coprecipitation temperature is40℃,the total concentration of mental ions is0.1mol/L,0.5%PEG600+0.5%SDBS as surfactants, the aging time is24hours, first washing with deionized water and then with anhydrous ethanol, calcination temperature is650℃calcination time is4hours. Under the confirmed reaction conditions, the catalysts prepared with the optimal conditions have better catalytic performance and the removal rate of SO2is78.7%.(3) The study on the catalytic performance of Ce0.7Ti0.3O2prepared under optimized conditions for CO+NO+SO2. indicates that, when temperature is500℃, airspeed is24000ml/(g·h), the composition of reaction gases is0.3%SO2+0.1%NO+0.7%CO, the removal rate of SO2is over91%, the removal rate of NO is over96%. Results of XRD show that the structure of Ce0.7Ti0.3O2remains unchanged after the catalytic reaction.