Low-Temperature NH 3 -SCR over Hierarchical MnO x Supported on Montmorillonite Prepared by Different Methods

作者：Xianlong Zhang, Shi Jin, Shiwen Liu, Yazhong Chen, Cheng Fang, Kui Wang, Xinyu Wang, Xueping Wu, Junwei Wang · 发表于：ACS Omega · 年份：2023 · DOI：10.1021/acsomega.3c00718 · 被引用次数：25 · 研究领域：Catalytic Processes in Materials Science、Ammonia Synthesis and Nitrogen Reduction、Gas Sensing Nanomaterials and Sensors

High Resolution Image Download MS PowerPoint Slide Hierarchical MnO x pillared or supported on montmorillonite were prepared by three methods, i.e., impregnation (IM), chemical precipitation (CP), and in situ deposition (SP). The catalysts were characterized by low-temperature N 2 adsorption (BET), XRD, XPS, SEM, TEM, H 2 -TPR, NH 3 -TPD, NO-TPD, TPSR, in situ DRIFTS, and evaluation of catalytic performance for NH 3 -SCR. The best catalytic performance was obtained for catalysts prepared by SP in terms of activity and selectivity, obtaining >90% NO conversion with >95% selectivity to N 2 in 100–300 °C and GHSV of 70,000 h –1 . Compared to IM and CP, SP greatly simplified catalyst preparation, resulting in higher BET surface areas; a spongy pore structure; more highly dispersed, pillared MnO x species; and higher density of acid sites distributed on catalysts surface, which all contributed to its superior performance for NH 3 -SCR. The activity for low-temperature NH 3 -SCR of manganese catalysts could be widely tailored by preparation methods.