通过分子模拟和实验在LTA/FAU热质中H2/N2的竞争性吸附机制
Zixu Dong1, Zhilu Wang1, Lina Zhang1
1School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, China.
Molecules (Basel, Switzerland)
|August 10, 2024
概括
在工业过程中,有效地分离 (H2) 和 (N2) 是至关重要的. 这项研究显示,N2与H2相比,对氧化物吸附点的亲和力更大,影响了分离效率.
科学领域:
- 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.
- 物理化学 物理化学
背景情况:
- 高效的 (H2) 和 (N2) 分离对于从工业尾气中生产高纯度至关重要.
- 石是气体分离的有希望的材料,因为它们的调节性结构和吸附性质.
研究的目的:
- 研究H2和N2混合物的吸附特性和竞争机制在LTA和FAU类型的热上.
- 提供H2-N2混合物在热石中吸附的分子理论基础.
主要方法:
- 吸附能力实验在各种温度 (77 K,298 K) 和压力 (0.1-10 bar) 下进行.
- 采用大法典蒙特卡罗 (GCMC) 模拟,利用H2双极和N2极化的力场.
- 实验验证证了应用力场的准确性.
主要成果:
- 与Na交换对应物 (Na-FAU,Na-LTA) 相比,与Ca交换的热石 (Ca-FAU,Ca-LTA) 相比,N2和H2负荷更高.
- 在77K的NaX上观察到最高的N2/H2吸附选择性,而在298K的NaA上则发生相反的情况.
- 尽管N2对框架氧原子有更大的亲和力,但H2的扩散率比N2高.
结论:
- 2和N2在热质中具有相似的吸附点,主要是框架氧原子和非框架.
- 由于H2和N2的亲和力和扩散率不同,这会影响它们在热石中的分离性能.
- 这项研究为H2-N2吸附提供了分子洞察力,有助于设计先进的分离材料.
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