Zn促进化学循环氨基合成,由LiH-Li2 NH对进行介导
Runze Wang1,2, Wenbo Gao1,2, Sheng Feng1,3
1Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China.
ChemSusChem
|July 18, 2023
概括
这项研究引入了作为化学循环氨合成 (CLAS) 的催化剂,显著提高了氨生产率. 新的Zn-LiH-Li2NH工艺增强了固化动力学,以有效地产生氨.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 化学循环氨合成 (CLAS) 通过避免竞争性吸附和间接的缩放关系,比传统方法具有优势.
- 之前的研究表明,使用或性土金属化物-化物配对与过渡金属催化剂低温氨合成.
研究的目的:
- 为了研究 (Zn) 对化-胺化物 (LiH-Li2NH) 介导的CLAS过程的影响.
- 探索通过添加 Zn.形成的新反应途径和中间体.
- 通过CLAS提高氨生产的效率和速度.
主要方法:
- 采用了经过修改的化学循环氨合成工艺,其中包含IIB组金属 (Zn).
- 分析了中间体的形成,如金属间化合物 (LixZny) 和三元金属化物 (LiZnN).
- 在350°C时测量了氨的生产速度和明显的激活能量.
主要成果:
- 添加 Zn 极大地改变了反应路径,形成 Li2NH,LixZny 和 LiZnN 的中间体.
- 在Zn-LiH-Li2NH介导的CLAS中,LiZnN和Li2NH充当有效的载体.
- 固定N2的明显激活能量从102kJ/mol降至50kJ/mol,氨产量增加了19倍,达到956μmol/g/h.
结论:
- 通过修改反应机制和载体物种,显著促进了LiH-Li2NH介导的CLAS的性能.
- 该Zn-LiH-Li2NH系统显示了N2固定的增强动力学,导致在低温下氨合成速率大幅增加.
- 这项研究突出了IIB组金属,特别是在推进化学循环氨合成技术方面的潜力.
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