A series of Cu (5 wt%) modified microporous zeolites (ZSM-5, Beta, MCM-22, MCM-49, and Y) was investigated for selective catalytic combustion of acrylonitrile (C₂H₃CN-SCC), associated with N₂ yield order of Cu-ZSM-5 (SiO₂/Al₂O₃ = 26) > Cu-MCM-49 > Cu-MCM-22 > Cu-Beta > Cu-Y. Various characterizations of XRD, N₂ adsorption, H₂-TPR, NH₃-TPD and XPS were employed to reveal structure-activity relationship. It was suggested that (i) isolated Cu cation acting as active center played a major role in C₂H₃CN-SCC; (ii) lowering SiO₂/Al₂O₃ ratio could enhance ion-exchanging capacity and thereby improve the zeolitic catalytic behavior; (iii) Cu-ZSM-5 (SiO₂/Al₂O₃ = 26) possessed the largest amounts of Cu cations as well as the highest Cu²⁺ → Cu⁺ redox ability, being responsible for its excellent catalytic behavior. C₂H₃CN-SCC mechanism over Cu-ZSM-5 was further investigated by in situ diffuse reflectance infrared Fourier transform spectroscopy (in-situ DRIFTS) and density functional theory (DFT) calculation. C₂H₃CN-SCC mainly followed an oxidation mechanism via intermediate of NCO in absence of H₂O; however, after an introduction of H₂O hydrolysis mechanism was dominated involving NH₃ intermediate. DFT simulation majorly focusing on NCO formation mechanism reveals that C₂H₃CN could be initially adsorbed on active center Cu of Cu-ZSM-5 through its N, associate with atomic C of CN being adsorbed with a dissociated atomic O. Such kind of adsorption mode greatly favored C₂H₃CN bond fracture to produce NCO, of which the energy barrier was calculated to be 17.0 kcal mol⁻¹. Mulliken charge transfer (CT) analysis was further conducted, based on which the electronic properties of active center Cu, zeolite framework and dissociated atomic O were well illustrated.

研究了一系列的Cu（5 wt％）改性微孔沸石（ZSM-5，Beta，MCM-22，MCM-49和Y）用于丙烯腈（C ₂ H ₃ CN-SCC）的选择性催化燃烧，以及Cu-ZSM-5（SiO ₂ / Al ₂ O ₃  ＝ 26）的N ₂屈服次序> Cu-MCM-49> Cu-MCM-22>Cu-β> Cu-Y。利用XRD，N ₂吸附，H ₂ -TPR，NH ₃ -TPD和XPS的各种表征方法揭示了结构-活性关系。建议：（i）分离出的铜阳离子作为活性中心在C ₂ H ₃ CN-SCC中起主要作用；（ii）降低SiO ₂ / Al₂ O _3的比例可以提高离子交换能力，从而改善沸石的催化性能。（iii）Cu-ZSM-5（SiO ₂ / Al ₂ O ₃  ＝ 26）具有最大量的Cu阳离子以及最高的Cu 2 ⁺  →Cu ⁺氧化还原能力，这归因于其优异的催化性能。通过原位漫反射红外傅里叶变换光谱（原位DRIFTS）和密度泛函理论（DFT）计算，进一步研究了Cu-ZSM-5上C ₂ H ₃ CN-SCC的机理。C ₂ H ₃ CN-SCC主要在不存在H的情况下通过NCO中间体遵循氧化机理₂ O; 但是，引入H ₂ O后，水解机理占主导地位，其中涉及NH ₃中间体。DFT模拟主要关注NCO的形成机理，结果表明C ₂ H ₃ CN最初可以通过其N吸附在Cu-ZSM-5的活性中心Cu上，而CN的原子C则被离解的原子O吸附。吸附模式极大地促进了C ₂ H ₃ CN键断裂而生成NCO，据计算其能垒为17.0 kcal mol ^-1。进一步进行了Mulliken电荷转移（CT）分析，在此基础上很好地说明了活性中心Cu，沸石骨架和离解的原子O的电子性质。