摘要
用傅里叶变换漫反射红外光谱法研究了原位合成的不同硅铝比的Cu ZSM 5 /堇青石整体式催化剂上一氧化氮的吸附态 ,以及温度和一氧化氮浓度对吸附态的影响 .结果表明 ,铜在整体式催化剂中主要以二价铜离子的形式存在 ,未发现一氧化氮在一价铜离子上的特征吸收峰 ;由二价铜的一氧化氮吸附物种衍生的Cu2 +(O) (NO)是与活性密切相关的物种 .
The adsorption of NO on in situ synthesized Cu ZSM 5/cordierite monolithic catalyst samples with different Si/Al ratios is studied by diffuse reflectance Fourier transform infrared spectroscopy at different NO partial pressure from ω =5×10 -4 to 2×10 -3 and temperatures from 298 K to 773 K. The Cu exists mainly in Cu 2+ state even at room temperature. No Cu +—NO is found under the conditions. Several N 2O species are observed on the catalyst surface as well as on the Cu/cordierite sample. It is supposed that there exists a copper zeolite substrate interaction on the in situ synthesized monolithic catalyst. The band at 2133 cm -1 is attributed to NO +—O lattice and only related to the zeolite matrix. A possible mechanism of NO decomposition over the Cu ZSM 5/cordierite monolithic catalyst is drawn.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2001年第3期245-249,共5页
关键词
ZSM-5分子筛
堇青石
整体式催化剂
傅里叶变换漫反射红外光谱法
一氧化氮
吸附态
分解
反应机理
催化活性
copper, ZSM 5 zeolite, cordierite, monolithic catalyst, diffuse reflectance Fourier transform infrared spectroscopy, nitrogen oxide, adsorption state, decomposition, reaction mechanism
