Catalytic urea hydrolysis by composite metal oxide catalyst towards efficient urea-based SCR process:performance evaluation and mechanism investigation  

作　　者：Yuchen Li Zhen Chen Xiangyu Zhang Kun Yang Lidong Wang Junhua Li 

机构地区：[1]MOE Key Laboratory of Resources and Environmental Systems Optimization,Department of Environmental Science and Engineering,North China Electric Power University,Beijing 102206,China [2]State Key Joint Laboratory of Environment Simulation and Pollution Control,School of Environment,Tsinghua University,Beijing 100084,China [3]Xi’an Thermal Power Research Institute Co.,Xi’an 710032,China

出　　处：《Frontiers of Environmental Science & Engineering》2023年第5期67-80,共14页环境科学与工程前沿（英文）

基　　金：supported by the Science and Technology Projects of China Huaneng Group Co.,Ltd.(No.HNKJ21-H15);the National Natural Science Foundation of China(No.22106084);the Special Projects of China Postdoctoral Science Foundation(No.2022T150350).

摘　　要：As a promising option to provide gaseous NH_(3) for SCR system,catalytic urea hydrolysis has aroused great attention,and improving surface area and activity of catalysis are the crucial issues to be solved for efficient urea hydrolysis.Therefore,a composite metal oxide(TiO_(2)@Al_(2)O_(3))catalyst was prepared by a simple hydrothermal method,with mesoporous alumina(γ-Al_(2)O_(3))as substrate.The results verify the mesoporous structure and submicron cluster of TiO_(2)@Al_(2)O_(3),with exposed crystal faces of(101)and(400)for TiO_(2)andγ-Al_(2)O_(3),respectively.The electronegativity difference of Ti4+and Al3+changes the charge distribution scheme around the interface,which provides abundant acid/base sites to boost the urea hydrolysis.Consequently,for an optimal proportioning with nano TiO_(2)content at 10 wt.%,the hydrolysis efficiency can reach up to 35.2%at 100℃ in 2 h,increasing by~7.1%than that of the blank experiment.^(13)C NMR spectrum measurements provide the impossible intermediate species during urea hydrolysis.Theoretical calculations are performed to clarify the efficient H_(2)O decomposition at the interface of TiO_(2)@Al_(2)O_(3).The result offers a favorable technology for energy-efficiency urea hydrolysis.

关 键 词：SCR Urea hydrolysis CATALYTIC Water dissociation ELECTRONEGATIVITY 

分 类 号：X701[环境科学与工程—环境工程]