修饰红泥中Pd和Fe之间的相互作用对二烯的催化分解的影响
Hongping Fang1,2, Wenjun Liang3, Chen Ma1
1Key Laboratory of Beijing on Regional Air Pollution Control, Beijing University of Technology, Beijing, 100124, China.
概括
改性红泥 (MRM) 支持 (Pd) 催化剂,以有效地氧化二烯. 0.3Pd/MRM催化剂表现出卓越的性能,归因于增强的表面氧和Fe3+含量,促进了电子转移和氧气流动性.
科学领域:
- 催化剂是一种催化剂.
- 环境化学环境化学
- 材料科学 材料科学 材料科学
背景情况:
- 红泥 (RM) 是生产中的一个重要的工业固体废物.
- 为挥发性有机化合物 (VOC) 氧化开发高效的催化剂对于环境修复至关重要.
研究的目的:
- 修改红色泥为 (Pd) 催化剂的支.
- 为了研究Pd/MRM催化剂的催化活性,用于二烯氧化.
- 阐明反应机制并确定影响催化性能的因素.
主要方法:
- 在修改红泥 (Pd/MRM) 催化剂上支持Pd的合成.
- 使用XPS,H2-TPR,FT-IR,O2-TPD,拉曼和TEM进行表征.
- 在不同温度下对多二氧化物的催化活性的评估.
- 在现场DRIFTS和GC-MS分析以研究反应中间体和机制.
主要成果:
- 0.3Pd/MRM催化剂表现出最佳的二氧化活性 (T50 = 175 °C,T100 = 200 °C).
- 在0.3Pd/MRM中,表面吸附氧气和Fe3+含量较高有利于二烯氧化.
- 在0.4Pd/MRM的PdO纳米粒子聚合对催化效率产生了负面影响.
- Pd-O-Fe相互作用增强了电子转移和表面吸附氧气的移动性.
结论:
- 改性红泥是Pd催化剂在二氧化中的可行的支持.
- 催化剂的性能与表面的氧物种,Fe3+含量和Pd分散度有关.
- 了解涉及和中间体的反应途径是优化过程的关键.
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