铜含量对Cu-SAPO-34催化剂NH3选择性催化还原NOx的影响
The effect of copper loading on NH3 selective catalytic reduction of NOx over Cu-SAPO-34 catalysts
张天天 1刘洋 2张恒 2郝彦衡 2侯坤明 2韩丽峰 2曾尚红 2王艳1
作者信息
- 1. 包头稀土研究院,内蒙古 包头 014030;内蒙古大学 化学化工学院,呼和浩特 010051
- 2. 内蒙古大学 化学化工学院,呼和浩特 010051
- 折叠
摘要
针对分子筛催化剂低温活性不佳的问题,采用一锅法原位合成了具有不同Cu负载量的Cu-SAPO-34催化剂,研究了催化剂的表面性质、Cu物种分布及种类对Cu-SAPO-34低温活性的影响,探究了NH3选择性催化还原NOx(NH3-SCR)的反应机理.研究结果表明,原位合成有利于SAPO-34骨架稳定,适量的Cu可以使所制备的催化剂具有多级孔道结构并以微孔为主导,有利于SCR反应.丰富的ZCuOH位点和稳定的酸位使0.2 Cu-SAPO-34催化剂具有优异低温SCR活性.经过机理分析发现,SCR反应在0.2 Cu-SAPO-34催化剂上遵循Eley-Rideal和Langmuir-Hinshelwood两种反应机理,并且在低温端时Eley-Rideal机理占主导地位.
Abstract
To address the problem of poor low-temperature activity of molecular sieve catalysts,Cu-SAPO-34 catalysts with different Cu loadings were synthesized in situ by a one-pot method,and the effects of catalyst surface properties,Cu species distribution and species on the low-temperature activity of Cu-SAPO-34 were analyzed.Furthermore,the reaction mechanism of NH3 selective catalytic reduction of NOx(NH3-SCR)were investigated.The results show that in situ synthesis is beneficial to SAPO-34 framework stabilization,and the appropriate amount of Cu can make the prepared catalysts to possess a multi-level pore structure dominated by micropores,which is beneficial to SCR reaction.The abundant ZCuOH sites and stable acid sites give the 0.2 Cu-SAPO-34 catalyst excellent low-temperature SCR activity.After mechanistic analysis,SCR reactions over 0.2 Cu-SAPO-34 catalysts both followed the Eley-Rideal and Langmuir-Hinshelwood reaction mechanisms,and the Eley-Rideal mechanism is dominant at low temperatures.
关键词
NH3-SCR/Cu-SAPO-34/活性物种/反应机理Key words
NH3-SCR/Cu-SAPO-34/active species/reaction mechanisms引用本文复制引用
基金项目
国家自然科学基金(21968020)
中国北方稀土(集团)高科技有限公司科技项目(BFXT-2021-D-0022)
白云鄂博稀土资源研究与综合利用全国重点实验室自主课题(BFXT-2022-D-0043)
出版年
2024
NETL
NSTL
万方数据