在金属有机框架上分离 styrene 和 ethylbenzene:具有不同吸附机制的类似结构
Michael Maes1, Frederik Vermoortele, Luc Alaerts
1Centre for Surface Chemistry and Catalysis, Katholieke Universiteit Leuven, Arenbergpark 23, B-3001 Leuven, Belgium.
Journal of the American Chemical Society
|October 15, 2010
概括
金属有机框架MIL-47和MIL-53 (((Al) 有效地将烯从乙中分离出来. 不同的吸附机制,MIL-47的非体,MIL-53的体,决定了烯的吸附作用.
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.
- 吸附科学 吸附科学
背景情况:
- 金属有机框架 (MOF) 为气体和液体分离提供可调节的多孔性.
- 乙和烯的分离在石化工业中至关重要.
- MIL-47和MIL-53是具有选择性吸附应用潜力的MOF.
研究的目的:
- 通过使用MIL-47和MIL-53 (((Al) MOFs,研究乙基和烯的分离机制.
- 在这些框架中阐明控制偏好的烯吸附的因素.
- 评估MIL-47和MIL-53的性能 () 在分离乙和烯混合物和去除杂质.
主要方法:
- 粉末X射线衍射实验分析客分子包装.
- 脉冲色谱用于在不同条件下确定分离因子.
- 吸附异热测量以量化吸收能力.
- 热力学分析以了解吸附热量.吸附热量.
主要成果:
- 无论是MIL-47还是MIL-53都表现出高吸附能力 (20-24重量%) 的乙和烯.
- 在MIL-47中显示,偏好的 styrene 吸附方式是通过一种非体的,独立于温度的双向包装机制.
- MIL-53 ((Al) 显示出偏好的 styrene 吸附,由因框架放松而产生的体差异驱动,具有温度依赖的分离因子.
- MIL-53 (((Al) 有效地从烯-乙基混合物中去除o-烯和烯等杂质.
结论:
- 以MIL-47和MIL-53的方法将乙基和烯分离,是通过不同的机制进行的.
- MIL-47使用独特的客人包装策略进行选择性分离.
- MIL-53 ((Al) 依赖于选择性吸附的框架灵活性和度差异.
- 这些MOF显示出在碳化合物分离和净化中的工业应用的前景.
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