Influence of framework n(Si)/n(Al) ratio on the nature of Cu species in Cu-ZSM-5 for $NH_3-SCR-DeNO_x$

These data relate to IR studies on nanosized Cu-containing ZSM-5 catalysts with different n(Si)/n(Al) ratios of 18.9–50.5. According to DR UV-Vis, TPR-H2, EPR, or FT-IR spectroscopy analyses, the amount of aggregated copper species increases with increasing the framework n(Si)/n(Al) ratio. The catalytic potential of the materials studied was evaluated in NH3-SCR-DeNOx process. The activity of the Cu-containing ZSM-5 with n(Si)/n(Al) ratio of 47.0—50.5 in the selective catalytic NO reduction with NH3 (NH3-SCR-DeNOx) significantly decreases compared to the other materials (n(Si)/n(Al) ratio of 18.9—19.6). The reaction mechanism has been discussed in light of the results of 2D COS (two-dimensional correlation spectroscopy) analysis of IR spectra and catalytic properties of the zeolites. The results make evident that enhanced activity of Cu-containing ZSM-5 in NH3-SCR-DeNOx is correlated with the formation of different NOx− under the experimental conditions.

本数据集围绕硅铝摩尔比（n(Si)/n(Al)）为18.9~50.5的不同规格纳米级含铜ZSM-5分子筛催化剂的红外光谱（Infrared, IR）研究展开。借助漫反射紫外-可见光谱（Diffuse Reflectance Ultraviolet-Visible Spectroscopy, DR UV-Vis）、氢气程序升温还原（Temperature Programmed Reduction-Hydrogen, TPR-H2）、电子顺磁共振波谱（Electron Paramagnetic Resonance, EPR）以及傅里叶变换红外光谱（Fourier Transform Infrared, FT-IR）等表征手段分析可知，团聚态铜物种的含量随分子筛骨架硅铝摩尔比的升高而增加。本研究通过氨选择性催化还原脱硝（NH3-SCR-DeNOx）反应评价了所制备材料的催化性能：硅铝摩尔比为47.0~50.5的含铜ZSM-5分子筛在该反应中的催化活性，相较于硅铝摩尔比为18.9~19.6的其余样品出现了显著下降。本研究结合红外光谱的二维相关光谱（Two-Dimensional Correlation Spectroscopy, 2D COS）分析结果与分子筛的催化性能，对该反应的机理进行了探讨。研究结果表明，含铜ZSM-5分子筛在氨选择性催化还原脱硝反应中提升的催化活性，与实验条件下不同NOx−物种的生成密切相关。

搜集汇总

背景与挑战

背景概述

该数据集基于IR研究，分析了不同骨架硅铝比（n(Si)/n(Al)=18.9–50.5）的纳米Cu-ZSM-5催化剂中铜物种的性质，发现聚集铜物种数量随硅铝比增加而增加。在NH3-SCR-DeNOx过程中，较高硅铝比（47.0–50.5）的催化剂活性显著降低，反应机制通过2D COS分析和催化性能结果进行探讨。