性土离子稳定子纳米锡集群用于甲脱
Zhenpu Lu1,2, Ran Luo1,3, Sai Chen1,2
1Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University China jlgong@tju.edu.cn chunlei.pei@tju.edu.cn.
加显著增强了脱的-锡催化剂,减少了失活并提高了的选择性. 这一发现为高效的催化过程提供了新的途径.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- /土金属是已知的异质催化,特别是脱 (PDH) 的促进者.
- 它们的促进作用背后的确切机制,特别是减少催化剂停用,尚未完全理解.
研究的目的:
- 调查 (Ca) 添加对 PDH (Pt-Sn) 催化剂的性能和失活的影响.
- 阐明Ca作为这种催化系统中的促进剂的运作原理.
主要方法:
- 在定义反应条件下对Pt-Sn和Pt-Sn-Ca催化剂进行实验性催化测试 (873 K, 16.5 h-1 WHSV).
- 分析催化剂结构和组成的特征化技术.
- 密度函数理论 (DFT) 模拟以模拟促进剂-催化剂相互作用.
主要成果:
- 加Ca减少了Pt-Sn催化剂的失活率从0.04h-1降至0.0098h-1在873 K.
- 该Pt-Sn-Ca催化剂实现了>96%的烯选择性,并在再生后保持高活性.
- Ca促进了Sn0和亚纳米Pt-Sn合金颗粒 (∼0.8nm) 的形成,增加了Pt电子密度并抑制了焦炭的形成.
结论:
- 作为结构促进剂,促进了Sn的减少,形成稳定,高度活性的Pt-Sn合金纳米粒子.
- 这些效应显著提高了脱过程中的催化剂稳定性,活性和选择性,为促进剂功能提供了洞察力.
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