对大气压增加Ar的动态建模分析N2-H2等离子体用于NH3的等离子体辅助催化合成
Zihan Lin1, Shota Abe1,2, Zhe Chen1
1Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States.
The journal of physical chemistry. A
|March 13, 2024
概括
的添加增强了非热等离子体中的氨合成,通过支持Eley-Rideal表面反应,而不是激发的分子. 这项研究阐明了在血辅助氨生产中的作用.
科学领域:
- 等离子体化学
- 化学动力学 化学动力学
- 催化剂是一种催化剂.
背景情况:
- 氨 (NH3) 的等离子体辅助合成是哈伯-博斯工艺的一个有希望的替代方案.
- 已知在N2-H2非热等离子体中的 (Ar) 稀释可以增强NH3的形成.
- 在Ar的增强作用背后的确切机制尚未完全理解.
研究的目的:
- 用零维动力模型阐明了对用等离子体辅助的氨催化合成的机械见解.
- 调查稀释在NH3生产的N2-H2非热等离子体中的作用.
- 挑战通常提出的涉及激发N2分子的机制.
主要方法:
- 空气压的零维动力模型Ar-N2-H2非热等离子体.
- 在室温和kHz频率下模拟一个同轴介电屏障放电石英羊毛包装床反应堆.
- 在不同度的Ar下分析反应途径,基因生成和物种解离.
主要成果:
- 氨的产生主要是由涉及表面NHx物种的Eley-Rideal (E-R) 表面反应,而不是激发的N2分子.
- 阿贡对NH3形成的增强主要不是由于与H物种的相互作用或激发的Ar原子增强的H基形成.
- 激发的Ar原子通过N2解离对气相N基生成有28%的贡献,其中电子冲击解离占主导地位.
- 阿贡物种在NH3解离中起到微不足道的作用.
结论:
- 在N2-H2等离子体中稀释Ar后增强的NH3形成主要是由Eley-Rideal表面反应驱动的,这与主流理论相反.
- 激发的Ar原子在N基生成中的作用很重要,但与电子冲击解离相比是次要的.
- 这种动态模型通过阐明Ar稀释的影响,为优化等离子体辅助氨合成提供了指导.
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