Methane Storage and Purification of Natural Gas in Metal-Organic Frameworks

Natural gas, primarily composed of methane (CH₄), represent an excellent choice for a potentially sustainable renewable energy transition. However, the process of compressing and liquefying CH₄ for transport and storage typically results in significant energy losses. In addition, in order to optimize its efficacy as a fuel, the CH₄ content of natural gas needs to be increased to a level of at least 97 % to ensure its quality and efficiency in various applications. Metal-organic frameworks (MOFs) represent a novel category of porous materials that possess exceptional capability in modifying pore size and chemical environment, making them ideally suited for the storage of CH₄ and the adsorption of propane (C₃H₈), ethane (C₂H₆), carbon dioxide (CO₂), nitrogen (N₂), and hydrogen sulfide (H₂S) to facilitate the purification process of CH₄ from natural gas. In this paper, we systematically summarize the mechanism by which MOF materials facilitate the storage of CH₄ and the purification of CH₄ from natural gas, leveraging the structural characteristics inherent to MOF materials. The focus of further research should also be directed towards the investigation of CH₄ storage by flexible MOFs, the resolution of the trade-off dilemma, and the commercial application of MOFs.