Quantitative discrimination of surface adsorbed NO_(x) species on CeO_(2) via spectrophotometry for SCR denitration investigation  

作　　者：Songil Sin Jiawei Ji Lijun Cheng Zhiwen Gu Chong Tan Kwangchol Ri Changjin Tang 

机构地区：[1]School of Environment,Nanjing Normal University,Nanjing,210023,China [2]Department of Mining Engineering,Kim Chaek University of Technology,Pyongyang,999093,Democratic People's Republic of Korea [3]Laboratory of Mesoscopic Chemistry of MOE,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing,20023,China [4]Institute of Chemical Engineering,Hamhung University of Chemical Engineering,Hamhung,Democratic People's Republic of Korea [5]Jiangsu Province Engineering Research Center of Environmental Risk Prevention and Emergency Response Technology,Nanjing,210023,China

出　　处：《Journal of Rare Earths》2024年第6期1066-1072,I0003,共8页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(22276097,21976081);the Major Scientificand Technological Project of Bingtuan(2018AA002)。

摘　　要：CeO_(2)-based catalysts are widely investigated for selective catalytic reduction(SCR)of NO with NH3.Interaction of NO/O_(2) with CeO_(2) generally produces two surface species,i.e.,nitrates and nitrites.However,the explicit quantification of these two species is still unresolved.Herein,we reported that spectrophotometry characterization was effective in determining surface adsorbed NOx species on CeO_(2) by measuring the corresponding ions(NO_(2)-and NO_(3)^(-))dissolved in aqueous solution.Experimental results show that both nitrate(-NO_(3))and nitrite(-NO_(2))species can be quantitatively evaluated and the accuracy is verified by calibrating with NOx-TPD result.Exclusive transfer of adsorbed NOx from catalyst surface to aqueous solution is confirmed and the dissolution process can be accelerated by ultrasonic treatment.Moreover,useful information related to evolution of surface NOx species under various conditions(O_(2) treatment,different adsorption temperature and duration)and over different catalysts(Fe_(2)O_(3),MnO_(2) and MnOx—CeO_(2))are provided.The result of present study demonstrates the potential of spectrophotometry for quantitative discrimination of surface NOx species on CeO_(2) and other oxide-based materials,which is conducive to mechanism analysis of SCR reaction.

关 键 词：Quantitative evaluation Spectrophotometry analysis Nitrate species Nitrite species CeO_(2)catalyst NH_(3)-SCR 

分 类 号：TQ426[化学工程]