Cu-ZSM-5催化分解NO的机理  

Mechanism of catalytic decomposition of NO by Cu-ZSM-5

作　　者：张欢 刘梁 史一林 乔晓磊[1] 金燕[1] ZHANG Huan;LIU Liang;SHI Yilin;QIAO Xiaolei;JIN Yan(School of Electrical and Power Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学电气与动力工程学院,山西太原030024

出　　处：《燃料化学学报（中英文）》2024年第6期831-838,共8页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(U1910214)资助。

摘　　要：Cu-ZSM-5催化分解NO具有潜在的应用前景。为揭示NO在Cu-ZSM-5催化剂的催化分解机理,基于密度泛函模拟了NO在Cu-ZSM-5催化剂中短距离Cu+对上的吸附,并提出副产物N_(2)O、NO_(2)辅助催化分解NO的反应路径。计算结果表明,双核铜氧物种是Cu基催化剂的重要活性中心。催化分解NO过程中,副产物NO_(2)在双核铜氧物种上的分解需要的活化能最高(为171.39 kJ/mol),N_(2)O分解需要86.92 kJ/mol的活化能垒,表明NO_(2)在活性位的分解难于N_(2)O的分解。N_(2)、O_(2)的解析分别吸收28.43、100.78 kJ/mol的热量,限速步骤为O_(2)的脱附。NO既作为反应物,同时又是催化过程中CuZSM-5催化剂活性中心实现氧化还原循环的关键还原剂。Catalytic decomposition of NO by Cu-ZSM-5 has potential application.In order to reveal the catalytic decomposition mechanism of NO over Cu-ZSM-5,the adsorption of NO over short-range Cu+pairs in Cu-ZSM-5 was simulated based on density functional theory.The reaction pathways of NO decomposition assisted by the byproducts N_(2)O and NO_(2)were also proposed.The results showed that the double nuclear copper-oxygen species was an important active centre.During the reaction,the highest activation energy(171.39 kJ/mol)was required for the decomposition of the by-product NO_(2)on the binuclear copper-oxygen species.While that for the decomposition of N_(2)O was 86.92 kJ/mol,suggesting that the decomposition of NO_(2)was more difficult.The desorption energy of N_(2)and O_(2)were 28.43 and 100.78 kJ/mol,respectively.The rate determining step was O_(2)desorption.NO acted both as a reactant and a key reductant for the redox cycle of the active centre of Cu-ZSM-5 during the process.

关 键 词：CU-ZSM-5 催化分解 双核铜氧物种 氧化还原循环 

分 类 号：X511[环境科学与工程—环境工程] X78