高氧空位尖晶石型锰基催化剂用于低温NH_(3)-SCR反应  

Spinel Mangane-Based Catalysts with High Oxygen Vacancy Used for NH_(3)-SCR Reaction at Low Temperature

作　　者：伍凡 田贺元 刘鹏[1,2] 孙立伟[1] 张一波[2,3] 杨向光 WU Fan;TIAN He-Yuan;LIU Peng;SUN Li-Wei;ZHANG Yi-Bo;YANG Xiang-Guang(State Key Laboratory of Rare Earth Resource Utilization,Jilin Province Key Laboratory of Green Chemistry and Process,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;University of Science and Technology of China,Hefei 230026,China;Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou 341000,China)

机构地区：[1]中国科学院长春应用化学研究所,稀土资源利用国家重点实验室,吉林省绿色化学与过程重点实验室,长春130022 [2]中国科学技术大学,合肥230026 [3]中国科学院赣江创新研究院,赣州341000

出　　处：《应用化学》2023年第5期697-707,共11页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金项目(Nos.22072141,22176185,22002150);中国科学院青年创新促进会人才项目(No.2018263);中国科学院重点部署项目(No.ZDRW-CN-2021-3);中国科学院赣江创新研究院自主部署项目(No.E055C003)资助;江西省双千计划(青年)项目(No.jxsq2020101047)。

摘　　要：制备了LiMn_(2)O_(4)、ZnMn_(2)O_(4)和CrMn_(2)O_(4)尖晶石型复合氧化物,测试了它们在50~450℃的氨择性催化还原(NH_(3)-SCR)氮氧化合物的活性,并考察了结构、不同金属元素和价态对NH_(3)-SCR活性的影响。使用物理吸附仪(BET)、X射线衍射仪(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线光电子能谱分析仪(XPS)、NH_(3)程序升温脱附(NH_(3)-TPD)和H2程序升温还原(H2-TPR)等对催化剂进行了表征,并对尖晶石催化剂的构效关系进行了研究。结果表明,活性最佳的LiMn_(2)O_(4)尖晶石催化剂在空速为6×10^(4)mL/(g·h),反应温度为150℃时有90%以上的NO转化率,且在100~400℃的温度范围内显示出80%以上的NO转化率,低温活性非常好,活性温度范围宽,而ZnMn_(2)O_(4)和CrMn_(2)O_(4)的脱硝活性则稍差,且二者的活性相近。在有水汽的条件下,LiMn_(2)O_(4)活性下降幅度较大,而ZnMn_(2)O_(4)和CrMn_(2)O_(4)活性只稍有下降,抗水性能较好。ZnMn_(2)O_(4)在150℃时转化率达90%,有水汽的条件下则比CrMn_(2)O_(4)活性更好。尖晶石ZnMn_(2)O_(4)在较宽的温度范围内有较好的NO转化率,且抗水性能强,具有较为良好的实用价值。Different spinel composite oxide catalysts,LiMn_(2)O_(4),ZnMn_(2)O_(4)and CrMn_(2)O_(4)are prepared and activities of the catalysts for selective catalytic reduction of NOx by NH_(3)(NH_(3)-SCR)are tested at 50~450℃.The effects of catalyst structure,metal elements and valence states on NH_(3)-SCR activity are investigated.The catalysts are characterized by physical adsorption instrument(BET),X-ray diffractometer(XRD),transmission electron microscope(TEM),scanning electron microscope(SEM),X-ray photoelectron spectroscopy(XPS),NH_(3)temperature-programmed desorption(NH_(3)-TPD)and H2 temperature-programmed reduction(H2-TPR),etc.The structure-activity relationship of spinel catalyst is also studied.The results show that:The LiMn_(2)O_(4)spinel catalyst has the best activity with more than 90%NO conversion at the space velocity of 6×10^(4)mL/(g∙h)at 150℃,and it shows more than 80%NO conversion at 100~400℃,demonstrating good low temperature activity and wide temperature range.However,the denitrification activity of ZnMn_(2)O_(4)and CrMn_(2)O_(4)is relative poor,and the two have similar activities.In the presence of water,the activity of LiMn_(2)O_(4)decreased greatly,while the activities of ZnMn_(2)O_(4)and CrMn_(2)O_(4)decreases slightly,showing better water resistance.The conversion rate of ZnMn_(2)O_(4)reach 90%at 150℃,which is better than that of CrMn_(2)O_(4)in the presence of water.Spinel ZnMn_(2)O_(4)has a good NO conversion rate in a wide temperature range and strong water resistance.

关 键 词：选择性催化还原 氨 氮氧化物 尖晶石氧化物 低温脱硝 废气处理 

分 类 号：O643.3[理学—物理化学]