Rational Design of a Novel Catalyst Cu-SAPO-42 for NH3-SCR Reaction
Rational Design of a Novel Catalyst Cu-SAPO-42 for NH3-SCR Reaction
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NH3-SCR 反应新型催化剂 Cu-SAPO-42 的合理设计
DOI：
10.1002/smll.202000902
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发表时间：
2020
期刊：
影响因子：
13.3
通讯作者：
Liu Zhongmin
中科院分区：
文献类型：
--
作者：
Yan Nana;Ma Chao;Cao Yi;Liu Xiaona;Cao Lei;Guo Peng;Tian Peng;Liu Zhongmin
铜交换的LTA型铝硅酸盐催化剂被认为是氨选择性催化还原氮氧化物(NH3-SCR)的有效催化剂。然而，合成LTA型分子筛(高硅LTA型铝硅酸盐及其类似物LTA型硅磷酸铝SAPO-42)不可避免地要使用昂贵的有机结构导向剂(OSDAs)和腐蚀性的氟化物介质。本论文通过一种新的RSS(Refine，Congate，and Search)方法对一系列廉价、商业化的OSDA进行了鉴定，这些OSDA已成功应用于无氟体系中SAPO-42的靶向合成。在此基础上，将Cu-SAPO-42催化剂用于NH3-SCR。在这些催化剂中，以2-丁氨基乙醇(BAEA)为OSDA的Cu-SAPO-42催化剂在800℃水热老化16h后仍表现出良好的活性，其水热稳定性远远好于硅和铜含量相当的商品化的Cu-SAPO-34催化剂。用电子顺磁共振(EPR)谱和Rietveld精修确定了活性Cu2+离子的位置。结果表明，活性Cu2+离子主要分布在单环中心附近。
Cu‐exchanged LTA‐type aluminosilicate catalyst has been considered as an efficient catalyst for the selective catalytic reduction of NOxwith ammonia (NH3‐SCR). However, expensive organic structure‐directing agents (OSDAs) and the corrosive fluoride medium are inevitably used to synthesize LTA‐type molecular sieve (high‐silica LTA‐type aluminosilicate and its analogue LTA‐type silicoaluminophosphate SAPO‐42). Herein, a series of cheap and commercialized OSDAs, which are successfully applied for the targeted synthesis of SAPO‐42 in the fluoride‐free system, are identified by a novel RSS (refine, summarize, and search) approach. Furthermore, Cu‐SAPO‐42 catalysts are utilized for NH3‐SCR. Among these catalysts, Cu‐SAPO‐42 prepared with 2‐(butylamino)ethanol (BAEA) as OSDA demonstrates the excellent activity even after hydrothermal aging at 800 °C for 16 h, which shows much better hydrothermal stability than the commercialized Cu‐SAPO‐34 catalyst with comparable Si and Cu contents. Electron paramagnetic resonance (EPR) spectroscopy and Rietveld refinement are performed to identify the locations of active Cu2+ions. It turns out that the active Cu2+ions are distributed near the center of single 6‐rings of theltacage.