N_(2)O催化分解的高效Ce/Co_(3)O_(4)催化剂研制及反应机制  

Development of efficient Ce/Co_(3)O_(4) catalysts and evaluation of reaction mechanism for catalytic decomposition of N_(2)O

作　　者：王俊霈 彭新月 龚圆钰 晏乃强[1] 马磊 WANG Junpei;PENG Xinyue;GONG Yuanyu;YAN Naiqiang;MA Lei(School of Environmental Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240)

机构地区：[1]上海交通大学环境科学与工程学院,上海200240

出　　处：《环境科学学报》2024年第12期295-305,共11页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.22176122);上海市自然科学基金(No.21ZR1431900);上海交通大学“深蓝计划”基金(No.SL2022ZD104)。

摘　　要：催化分解是减少N_(2)O温室气体排放的主要方法.研究合成出系列Ce/Co_(3)O_(4)催化剂,实现了低温下N_(2)O催化去除.催化性能结果表明,20%Ce/Co_(3)O_(4)具有最好的催化活性,在390℃时能够实现N_(2)O完全分解.同时,20%Ce/Co_(3)O_(4)的表观活化能从Co_(3)O_(4)的88.0 kJ·mol^(-1)降低到57.2kJ·mol^(-1).在含H_(2)O和O_(2)条件下,20%Ce/Co_(3)O_(4)依然表现出良好的稳定性,具备实际应用潜力.材料表征结果证实,引入CeO_(2)促进了Ce^(4+)+Co^(2+)←→Ce^(3+)+Co^(3+)氧化还原循环,有利于活性位点的再生,这是催化剂性能提升的主要原因.In situ DRIFTS和催化反应动力学结果表明,20%Ce/Co_(3)O_(4)上N_(2)O的分解遵循一级反应,催化剂表面N-O键的解离是反应的速率控制步骤.Direct catalytic decomposition offers a viable approach to mitigate N_(2)O pollution,which is an essential greenhouse gas.In this study,a series of Ce/Co_(3)O_(4) catalysts were meticulously synthesized,accomplishing remarkable N_(2)O removal under low temperatures.Catalytic performance tests revealed that 20%Ce/Co_(3)O_(4) catalysts exhibited superlative catalytic activity,achieving complete decomposition of N_(2)O at 390℃.Meanwhile,the apparent activation energy of 20%Ce/Co_(3)O_(4) was dramatically reduced from 88.0 kJ·mol^(-1)for Co_(3)O_(4) to 57.2 kJ·mol^(-1).In the presence of H_(2)O and O_(2),20%Ce/Co_(3)O_(4) catalysts maintained robust stability,highlighting their potential advantage in practical applications.Material characterization results confirmed that the introduction of CeO_(2) promoted the redox cycle of Ce^(4+)+Co^(2+)←→Ce^(3+)+Co^(3+),facilitating the regeneration of active sites.It was the primary reason for the improved catalytic performance.In situ DRIFTS and catalysis reaction kinetics confirmed that the decomposition of N_(2)O over20%Ce/Co_(3)O_(4) catalysts was the first-order reaction and the dissociation of the N-O bond on the surface of the catalysts was the rate-determining step of the reaction.

关 键 词：氧化亚氮 直接催化分解 钴基催化剂 稀土氧化铈 反应机制 

分 类 号：X511[环境科学与工程—环境工程]