Ce改性的OMS-2催化剂的SCR-CO脱硝特性研究

摘要采用水热法一步合成了Ce改性的OMS-2催化剂(Ce_x-OMS-2),并在固定床微反应器上评估其催化CO选择性还原NO的性能。结果表明,Ce_0.08-OMS-2在0.05%NO(所有气体均为体积分数,下同)、0.10%CO、5.00%O₂,N₂为平衡气体的条件下,在175~300 ℃下实现100%的NO转化率,N₂选择性在175 ℃达到最大的93.2%。通过XRD、BET、XPS、NH₃-TPD及H₂-TPR对催化剂进行表征,探究活性金属Ce的掺杂对OMS-2催化剂的物理化学性质的影响。研究表明,较低的团聚和结晶度、较大的比表面积和孔容、较小的平均孔径、更多的表面氧空位和Mn⁴⁺和表面强Brønsted酸有利于Ce_x-OMS-2催化剂低温活性的增强。

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	蔡晨
	宁淑英
	陈佳音
	付维
	周皞
	苏亚欣

关键词：氮氧化物选择性催化还原 CO OMS-2催化剂 Ce

Abstract： The Ce-modified OMS-2 catalysts (Ce_x-OMS-2) were synthesized by one-step hydrothermal synthesis method, and its performance of selective catalytic reduction of NO by CO (SCR-CO) was evaluated in a fixed bed micro-reactor. The outcomes demonstrated that Ce_0.08-OMS-2 achieved 100% NO conversion at 175—300 ℃ under the condition of 0.05%NO, 0.1%CO, 5%O₂ and N₂ as equilibrium gases, and the N₂ selectivity reached a maximum of 93.2% at 175 ℃. By using XRD, BET, XPS, NH₃-TPD and H₂-TPR to characterize the catalysts, the effects of doping the active metal Ce on the physicochemical characteristics of OMS-2 catalysts were investigated. The results demonstrate that the improvement of the low-temperature activity of the Ce_x-OMS-2 catalyst is facilitated by lower agglomeration and crystallinity, larger specific surface area and pore volume, smaller average pore size, enhanced surface oxygen vacancies, increased Mn⁴⁺ concentration, and more Brønsted acid.

Keywords： NO_x selective catalytic reduction CO OMS-2 catalyst Ce

Received 2023-06-04;

Fund:国家自然科学基金项目(52276103)。

Corresponding Authors: 苏亚欣,教授,E-mail:suyx@dhu.edu.cn。 Email: suyx@dhu.edu.cn

About author: 蔡晨(1998—),女,硕士研究生,现从事燃烧污染物控制方面的研究。

引用本文:

蔡晨, 宁淑英, 陈佳音, 付维, 周皞, 苏亚欣.Ce改性的OMS-2催化剂的SCR-CO脱硝特性研究[J]. 化学工业与工程, 2024,41(6): 61-69

CAI Chen, NING Shuying, CHEN Jiayin, FU Wei, ZHOU Hao, SU Yaxin.Study on SCR-CO performance of Ce modified OMS-2 catalysts[J]. Chemcial Industry and Engineering, 2024,41(6): 61-69

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