CeMn氧化物催化剂的制备及其对甲苯的催化降解性能

采用草酸沉淀法合成了铈锰氧化物(CeMn氧化物)催化剂,在固定床反应器中考察了不同Ce-Mn摩尔比、空速对CeMn氧化物催化剂催化降解甲苯效果的影响,通过XRD、SEM、XPS等技术表征了催化剂的理化性质.实验结果表明:当n(Ce):n(Mn)=1:3时得到的Ce1Mn3催化剂降解甲苯的活性最佳,T50=198℃,T9...

Preparation of cerium-manganese oxide catalysts and their catalytic activities to toluene degradation

The cerium-manganese oxidecatalysts （CeMn oxides）were synthesized byoxalic acid precipitation method. The effects of mole ratio of cerium to manganese and airspeed oncatalytic degradation of toluene were investigated in a fixed bed reactor. The physical and chemical properties of CeMn oxides were characterized by XRD,SEM and XPS. The experimental results show that：The catalytic activity of Ce₁Mn₃ with n（Ce）∶n（Mn）=1∶3 for toluene degradation is the highest,where in T₅₀=199 ℃ and T₉₀=249 ℃,and has good stability;With the increase of airspeed,the catalytic activity of Ce₁Mn₃ to toluene degradation decreased. The characterization results indicate that：The concentration of oxygen vacancy on the surface of CeMn oxidesis increased with the Ce-Mn solid solution formed from CeMn oxides,so that the flow transmission of oxygen species inside and on the surface of the catalystis accelerated;The reduction peak of the catalyst shifts to the low temperature direction under synergy of Ce oxide and Mn oxide,and the low temperature activity of CeMn oxides is more excellent.