摘要
采用浸渍法制备了Mo/Mn-TiO_2催化剂并用于实验室固定床氨选择性催化还原NO过程(NH3-SCR),NO脱除实验结果表明,在160~440℃温度范围内,单独掺入Mn即可大幅提高催化脱硝活性,且在160~280℃温度范围内脱硝效率>90%,使得脱硝活性温度窗口显著向低温偏移;继续掺入Mo后,脱硝效率在120~200℃温度范围内存在不同程度下降,但在240~440℃温度范围内则得到进一步改善;Mn-TiO_2催化剂脱硝活性随SO_2浓度的升高而降低,且在较低反应温度下SO_2中毒程度愈为明显;继续掺入Mo后其抗SO_2中毒性能得到较大提升,240℃反应温度、SO_2体积分数<0.05%时脱硝效率仍保持90%以上。结合BET、EDX、H_2-TPR、XRD和XPS等现代分析技术对催化剂的孔隙结构、表面元素分布、反应活性及特征元素形态等进行了系统表征,阐明了Mo/Mn-TiO_2催化剂的脱硝及抗SO_2中毒机理。
Mo/Mn-TiO2oxides catalysts have been prepared by impregnation method and employed to selective catalytic reduction of NO with ammonia(NH3-SCR)on a laboratory fixed-bed.Experimental results of NO removal showed that,in the temperature range of160-440℃,the dopping of Mn alone can significantly improved the catalytic activity of denitrification,and the NO conversion efficiency was more than90%between160-280℃,which shifted the active temperature window to the low temperature observably.With the further doping of Mo,there were different degrees of drop on the NO conversion rate in the temperature of120-200℃,but the NO conversion rate can be further improved at240-440℃;The de-NOx activity decreased with the increase of SO2concentration on Mn-TiO2catalyst,and the SO2resistance dropped more sharply at lower reaction temperature.However,the resistance to SO2poisoning was greatly improved after the addition of Mo,and the efficiency of de-NOx is still more than90%at240℃when the SO2concentration was below0.05%.BET,EDX,H2-TPR,XRD and XPS were used to characterize the pore structure,surface elements distribution,reaction activity and the morphology of the catalyst systematically,and the mechanism of de-NOx and SO2resistance of Mo/Mn-TiO2catalyst was clarified.
作者
陈亚南
段钰锋
朱纯
周强
胡鹏
李春峰
王双群
CHEN Yanan;DUAN Yufeng;ZHU Chun;ZHOU Qiang;HU Peng;LI Chunfeng;WANG Shuangqun(Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,School of Energy and Environment,Southeast University,Nanjing 210096,Jiangsu,China)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2017年第8期2941-2948,共8页
Chemical Industry and Engineering Progress
基金
国家自然科学基金(51376046,51576044)
江苏省普通高校研究生科研创新计划(CXZZ13_0093,KYLX_0115,KYLX_0184,KYLX15_0071)
东南大学优秀博士学位论文培育基金(YBJJ1505)
国家重点研究开发计划(2016YFB0600604)项目
关键词
固定床
选择性催化还原
催化剂
脱硝活性
抗SO2性能
fixed-bed
selective catalytic reduction(SCR)
catalyst
denitrification activity
SO2 resistance
