Enhancing Ethane/Ethylene Separation Performance in Two Dynamic MOFs by Regulating Temperature-Controlled Structural
1Beijing Key Laboratory for Green Catalysis and Separation and Department of Environmental Chemical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China.
Inorganic Chemistry
|December 19, 2022
Summary
Two dynamic metal-organic frameworks, BUT-111 and BUT-112, enable efficient purification of ethylene from ethane. These materials exhibit ultramicropores and reversed adsorption behavior, achieving high-purity ethylene in a single step.
Area of Science:
- Materials Science
- Chemical Engineering
- Separation Science
Background:
- Ethane/ethylene separation is crucial in the chemical industry due to similar properties.
- Effective adsorbents require precise pore apertures for C2H6/C2H4 separation.
Purpose of the Study:
- To develop novel adsorbents for efficient C2H4 purification from C2H6/C2H4 mixtures.
- To investigate the impact of framework interpenetration on adsorption performance.
Main Methods:
- Synthesis of two dynamic pillar-layered metal-organic frameworks (MOFs): BUT-111 and BUT-112.
- Characterization of their isomorphic frameworks and varying degrees of interpenetration.
- Evaluation of their adsorption behavior for C2H6/C2H4 separation under different temperatures.
Main Results:
- BUT-111 and BUT-112 exhibit dynamic behavior, forming ultramicropores upon activation.
- Both MOFs demonstrate reversed adsorption order for C2H6 and C2H4, enabling one-step C2H4 purification.
- Selectivity increases with decreasing temperature; enhanced interpenetration in BUT-112 improves purification.
Conclusions:
- Dynamic pillar-layered MOFs offer a promising strategy for challenging C2H6/C2H4 separations.
- Tunable interpenetration is key to optimizing MOF performance for C2H4 purification.
- BUT-111 and BUT-112 show potential for industrial application in C2H4 purification across a wide temperature range.
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