Fluorine-Functionalized Pore-Space-Partitioned Metal-Organic Frameworks for One-Step Methane Purification.
Jia-Yao Liu1, Li-Qiu Yang1, Yan-Fei Li1
1Key Laboratory of Applied Surface and Colloid Chemistry (MOE), Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
Inorganic Chemistry
|March 4, 2026
Summary
New metal-organic frameworks (MOFs) with synergistic pore engineering efficiently separate ethane and propane from natural gas. Fluorine functionalization enhances C-H···π and C-H···F interactions for high-purity methane recovery.
Area of Science:
- Materials Science
- Chemical Engineering
- Separation Science
Background:
- Efficient separation of ethane (C2H6) and propane (C3H8) from natural gas is crucial for purification.
- Current methods face challenges in selectively removing valuable hydrocarbons from methane (CH4).
Purpose of the Study:
- To develop advanced metal-organic frameworks (MOFs) for selective ethane and propane removal from natural gas.
- To investigate the impact of synergistic pore engineering (pore space partition and fluorine functionalization) on separation performance.
Main Methods:
- Synthesized fluorine-functionalized, pore-space-partitioned MOFs (SNNU-707/-708) with varying trifluoromethyl (-CF3) group concentrations.
- Performed single-component gas adsorption isotherm measurements to evaluate adsorption capacities.
- Utilized Ideal Adsorbed Solution Theory (IAST) and breakthrough experiments to assess selectivity and separation efficiency.
- Employed Grand Canonical Monte Carlo (GCMC) simulations to understand the underlying interaction mechanisms.
Main Results:
- SNNU-707/-708 exhibited significantly higher adsorption capacities for C2H6 and C3H8 compared to CH4.
- IAST calculations showed high selectivity values for C3H8/CH4 (up to 116.6) and C2H6/CH4 (up to 17.0).
- Breakthrough experiments achieved high-purity CH4 (>99.5%) from ternary mixtures, demonstrating practical separation capability.
- The MOFs maintained structural integrity and separation performance under high humidity (98% RH), crucial for wet natural gas.
Conclusions:
- Synergistic pore engineering combining pore space partition and fluorine functionalization in MOFs is highly effective for selective alkane separation.
- Enhanced C-H···π and C-H···F interactions within the fluorine-functionalized pore environments are key to the observed separation performance.
- These MOFs offer a promising solution for efficient natural gas purification, especially under humid conditions.
