相关实验视频
Updated: Feb 11, 2026

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Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
27.4K
氨在铁表面的反应机制和动力学
Jin Qian1, Qi An1,2, Alessandro Fortunelli1,3
1Materials and Process Simulation Center (MSC) , California Institute of Technology , Pasadena , California 91125 , United States.
Journal of the American Chemical Society
|April 28, 2018
概括
研究人员利用量子力学优化了哈伯-博什的氨合成过程. 这项研究预测了反应机制和动力学,以提高肥料生产的能源效率.
科学领域:
- 催化剂
- 化学工程
- 材料科学
背景情况:
- 哈伯-博斯工艺对于氨合成至关重要,
- 尽管进行了广泛的优化,但该过程消耗了全球2%的能源,因此需要提高效率.
研究的目的:
- 通过预测反应机制和动力学来加速氨合成效率的提高.
- 提供使用计算方法优化哈伯-博什过程的指导方针.
主要方法:
- 利用量子力学预测氨合成的反应机制和动力学.
- 采用预测反应障碍的动力蒙特卡洛模型.
- 将模型预测与673 K和20 atm的单晶实验数据进行比较.
主要成果:
- 在氨合成中准确预测所有反应障碍的自由能量.
- 预测和实验催化速率之间非常一致.
- 每个地点预测的转机频率 (TOF) 为17.7秒,与实验TOF的10秒-1非常相似.
结论:
- 量子力学预测与动力学建模相结合,准确地描述了Fe ((111) 上的氨合成.
- 这种方法为能源密集的哈伯-博斯工艺提供了进一步优化的途径.
- 这些发现支持开发更节能的氨生产方法.
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