基于碳的纳米孔膜中的纯和甲透:吸附异温和透实验
Matthis Kurth1, Mudassar Javed2, Thomas Schliermann1
1DBFZ Deutsches Biomasseforschungszentrum Gemeinnützige GmbH, 116, 04347 Leipzig, Germany.
Membranes
|June 26, 2024
概括
这项研究详细介绍了纳米孔碳膜上和甲的吸附和透. 观察到吸附率较低,表面扩散系数计算为膜系统设计.
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:
- 准确的吸附和透数据对于设计气体分离膜系统至关重要.
- 现有的关于 (H2) 和甲 (CH4) 在高温下对碳材料的吸附的数据是有限的.
- 纳米孔径碳膜为高效的气体分离应用提供了潜力.
研究的目的:
- 实验性地确定H2和CH4在特定的基于碳的纳米孔膜上的吸附行为.
- 为了研究这些气体在高温下通过膜的透特性.
- 计算H2和CH4的表面扩散系数,以协助膜系统建模.
主要方法:
- 对纯H2和CH4进行了吸附实验,温度为90°C~120°C,压力高达45bar.
- 兰慕尔吸附异热模型被用来适应实验吸附数据.
- 单元透实验在高达220°C的温度下进行,随后使用Maxwell-Stefan表面扩散模型进行分析.
主要成果:
- 兰穆尔模型为吸附数据提供了最合适的方法.
- 在研究的纳米多孔碳上,H2和CH4的吸附率与文献价值相比显著较低.
- 计算的麦克斯韦尔-斯蒂芬表面扩散系数 (Dis) 与实证模型一致,验证了它们在未来设计中的使用.
结论:
- 这项研究为CH4和H2在这种特定的纳米孔状碳材料上提供了宝贵的,以前无法获得的吸附数据.
- 确定的表面扩散系数适用于多组件建模,有助于分析和设计膜分离系统.
- 这些发现有助于理解纳米孔碳膜中的气体运输现象,并为潜在的工业应用做出贡献.
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