文献类型：期刊文献

英文题名：Generating Silicon-Rich AFX Zeolite Using Rigid Diquaternary Alkylammonium Structure Directing Agent Towards Stable Selective Catalytic Reduction of NOx by NH3

作者：Shi, Zheru[1]; Sun, Han[2]; Wang, Lei[3]; Deng, Quanzheng[4]; Gong, Chen-Xin[1]; Han, Lu[4]; Li, Kaixiang[5]; Deng, Wei[6]; Zhu, Yi-An[1]; Li, Zhenguo[5]; Chen, Haijun[2]; Zhu, Kake[1]

机构：[1] UNILAB, State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China; [2] Department of Electronics, Tianjin Key Laboratory of Photo-Electronic Thin Film Device and Technology, Nankai University, Tianjin, 300071, China; [3] School of Chemistry and Molecular Engineering, Nanjing Tech University, South Puzhu Rd. 30, Nanjing, 211816, China; [4] School of Chemical Science and Engineering, Tongji University, Shanghai, 200092, China; [5] National Engineering Laboratory for Mobile Source Emission Control Technology, China Automotive Technology & Research Center Co. Ltd, Tianjin, 300300, China; [6] School of Optoelectronic Materials and Technology, Jianghan University, Wuhan, 430056, China

年份：2023

外文期刊名：SSRN

收录：EI(收录号：20230398356)

语种：英文

外文关键词：Catalyst activity - Hydrothermal synthesis - Nitrogen oxides - Selective catalytic reduction - Silicon - Zeolites

摘要：New synthetic protocols to manipulate Si/Al ratios of small pore zeolites hold promise to find better selective NOx reduction catalyst using NH3 as reducing agent (NH3-SCR). AFX zeolite as NH3-SCR catalyst is currently impeded by the insufficient hydrothermal stability owing to the low Si/Al ratio. In this contribution, we report the synthesis of AFX zeolite using N,N-(1,4-phenylenebis(methylene))bis(N,N-diethylethanaminium) as organic structure directing agent (OSDA) to increase the framework Si/Al ratio to 7.8, giving rise to a marked enhancement of hydrothermal stability to withstand hydrothermal aging at 850 oC for up to 10 h. The increase in Si/Al ratio for AFX zeolite minimizes catalytic cycle driven by Br?nsted acid site and broadens high temperature operation window (150-520 oC) for Cu-exchange catalyst. Moreover, the hydrothermally aged Cu-AFX catalyst exhibits comparable catalytic activity to that of the fresh catalyst owing to Cu re-distribution that reinforced the framework stability. ? 2023, The Authors. All rights reserved.