磁性铁钛催化剂的制备及其NH_3选择性催化还原NO性能  

Selective Catalytic Reduction of NO_x with NH_3 over Magnetic Iron-Titanium Mixed Oxide Catalysts

作　　者：武超[1] 熊志波[1] 周飞[1,2] 白鹏[1] 金晶[1] 丁旭春 

机构地区：[1]上海理工大学能源与动力工程学院,上海200093 [2]江苏国信靖江发电有限公司,靖江214500

出　　处：《上海理工大学学报》2016年第5期427-432,共6页Journal of University of Shanghai For Science and Technology

基　　金：国家自然科学基金资助项目(51406118);国家科技支撑计划(2015BAA04B03);上海市基础研究重点项目(14JC404800)

摘　　要：利用微波热解辅助共沉淀方法制备磁性铁钛复合氧化物催化剂,探讨了钛掺杂对铁氧化物SCR（选择性催化还原）脱硝活性的影响规律,并借助XRD（X射线衍射）、N2吸附研究钛掺杂前后铁氧化物晶相和微观孔隙结构的变化趋势.结果表明：微波热解辅助共沉淀方法制备的单一铁氧化物表现出强烈的α-Fe2O3晶相,掺杂钛会提高铁氧化物的稳定性;当钛掺杂物质的量比为0.25时,铁钛复合氧化物存在γ-Fe2O3和α-Fe2O3两种晶相;钛掺杂可细化铁氧化物孔径,增大其比表面积和比孔容,从而提高其中低温NH3-SCR脱硝性能,合适的钛掺杂物质的量比为0.25;在空速比为60 000/h条件下,275-00℃区间Fe0.75Ti0.25Oz取得了高于90%的NOx转化率.Magnetic iron-titanium mixed oxide catalysts were prepared through the co-precipitation assisted by microwave-pyrolysis.The influence of Ti doping on the selective catalytic reduction of NOx over iron oxide was investigated,and the crystal phases and microscopic pore structure of iron oxides after the doping of titanium were also studied by XRD（X-ray diffraction）and N_2 adsorption-desorption test.The results indicate that a strong crystal phase ofα-Fe2O3 appears within iron oxides prepared through the co-precipitation assisted by microwave-pyrolysis.The addition of titanium can increase the thermal stability of iron oxide,meanwhile,iron-titanium mixed oxide catalysts show the crystal phase of γ-Fe2O3 andα-Fe2O3 when the molar ratio of Ti is 0.25.The pore size of iron oxides can be refined,and its Brunauer-Emmett-Teller surface and pore volume are increased after the doping of titanium oxide.Thereby its NH_3-SCR activity is improved,and the optimum molar ratio of titanium oxide is 0.25.Under the condition of 60 000/h gas hourly spacevelocity,more than 90% of NOxconversion can be achieved over Fe0.75Ti0.25 Ozat the temperature of 275~400 ℃.

关 键 词：选择性催化还原 Γ-FE2O3 催化剂 NOx 钛 

分 类 号：TK16[动力工程及工程热物理—热能工程]