显著的N2-选择性增强NH3-SCR超过HPMo修饰的MnCo-BTC@SiO2催化剂
Songjin Ko1, Xiaolong Tang2, Fengyu Gao2
1Department of Environmental Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China; Department of Chemistry, Pyongyang University of Architecture, Pyongyang, DPR of Korea.
Journal of environmental sciences (China)
|December 22, 2023
概括
聚酸盐修饰增强了MnCo-BTC@SiO2催化剂,用于选择性催化降低NOx. 这通过增加表面酸度和优化氧化还原特性来提高氨的选择性催化还原性能和N2选择性.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 环境化学环境化学
背景情况:
- 氧化物 (NOx) 的选择性催化还原 (SCR) 对环境保护至关重要.
- 开发具有高N2选择性和低温活性的高效催化剂仍然是一个挑战.
研究的目的:
- 为了提高MnCo-BTC@SiO2催化剂的N2选择性,使用聚酸盐 (HPMo) 修改来减少NOx.
- 阐明HPMo修饰增强催化性能的机制.
主要方法:
- 合成具有不同HPMo度的MnCo-BTC@SiO2催化剂.
- 使用X射线光电子光谱学 (XPS),H2温度编程减少 (H2-TPR),NH3温度编程脱吸 (NH3-TPD) 和现场扩散反射红外里埃变换光谱学 (现场DRIFTS) 进行了表征.
- 对NOx减排的催化性能进行评估.
主要成果:
- MnCo-BTC@SiO2-0.75催化剂显示出最佳的NH3-SCR性能 (在200-300°C时约95%) 和N2选择性 (>在100-300°C时80%).
- HPMo修改优化了氧化还原能力和表面酸度,增强了NH3的吸附和活性.
- 通过抑制NH物种和氨吸附物种的深度脱,HPMo修饰抑制了N2O形成.
结论:
- 聚酸盐修饰是一种有效的策略,可以提高MnCo-BTC@SiO2催化剂的低温催化性能和N2选择性,以减少NOx.
- 性能提升归因于表面酸度的提高,氧化还原性能的优化以及控制的氨吸附/激活通路.
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