摘要
以H_2O_2为氧化剂对NO进行低温氧化脱硝,考察了非催化和纳米TiO_2催化作用下的H_2O_2氧化低温脱硝性能;并以纳米TiO_2为载体,采用等体积浸渍法掺杂过渡金属氧化物CeO_2进行改性,制备了一系列CeO_2/TiO_2催化剂,探究了其催化作用下H_2O_2的氧化脱硝性能,并筛选获得了催化剂的最佳CeO_2负载量;进一步针对最优催化剂,考察了不同烟气工况对催化剂活性的影响,并进行了XRD、H2-TPR以及XPS等表征分析.表征结果显示,CeO_2的负载量会影响催化剂中晶格氧的含量,晶格氧相对含量的增加有利于氧化还原反应中的电子传递,这是促进H_2O_2活化分解的关键.实验结果表明,CeO_2/TiO_2催化剂能有效促进H_2O_2的活化分解实现低温脱硝,且CeO_2负载量为3%wt时,催化活性最高;在烟温为160℃、[H_2O_2]/[NO]物质的量比为2以及空速为30000 h-1时,NO转化率最高可达76%.
H2O2 was employed as an oxidant for the low temperature oxidative denitration.Experiments were conducted to determine the denitration properties of H2O2 in non-catalyzed and nano TiO2-catalyzed processes.In addition,a series of CeO2/TiO2 catalysts were prepared by incipient wet impregnation method,with CeO2 as the active component and nano TiO2 as the carrier.H2O2-based oxidative denitration experiments were performed to determine the optimal CeO2 loading on the catalyst.Based on the optimal CeO2/TiO2 catalyst,the influence of flue gas conditions on catalyst activity was investigated.The characterization analyses of XRD,H2-TPR and XPS showed that the increase of CeO2 loading was favorable for the formation of lattice oxygen,which was beneficial for the electron transfer in the redox reactions.Therefore,increase of lattice oxygen was the key to promote the decomposition of H2O2.The experimental results indicated that the CeO2/TiO2 catalyst could effectively promote the activation and decomposition of H2O2 for low temperaturedenitration.The best catalytic performance was obtained at the CeO2 loading of 3% wt.Under the flue gas temperature of 160℃,[H2O2]/[NO]molar ratio of 2 and space velocity of 30000 h-1,the NO conversion the reached as high as 76%.
作者
王琦
陆强
仇志超
傅玉
唐诗洁
董长青
杨勇平
WANG Qi;LU Qiang;QIU Zhichao;FU Yu;TANG Shijie;DONG Changqing;YANG Yongping(National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, Beijing, 102206, China)
出处
《环境化学》
CAS
CSCD
北大核心
2018年第6期1253-1263,共11页
Environmental Chemistry
基金
国家973项目(2015CB251501)
北京市科技新星(Z171100001117064)
中央高校基本科研业务专项资金(2016YQ05
2015ZZD02)资助~~
