Shape‐Matched Nonpolar Pore Surfaces Enhance Alkane Recognition Toward Natural Gas Upgrading

Efficiently removing C₃H₈ and C₂H₆ from natural gas remains a formidable challenge in meeting industrial purification demands. Traditional strategies have primarily focused on subtle polarizability differences among alkane molecules, there have been no reported efforts that exploit their substantial shape disparities for separation purposes. Hence, we customized a two-dimensional (2D) metal-organic framework (MOF), Zn-BPDP, featuring zigzag aromatic pore channels. Zn-BPDP achieves specific capture of V-shaped C₃H₈ and linear C₂H₆ through the synergistic effect of shape-matched and nonpolar pore surfaces. Ultimately, Zn-BPDP exhibits considerable C₃/C₂ adsorption capacities, along with outstanding C₃H₈/CH₄ and C₂H₆/CH₄ ideal adsorbed solution theory (IAST) selectivities. Under harsh simulated industrial conditions, including high flow rate (4 mL min^-1), elevated temperature (318 K), and saturated humidity (RH = 100%), Zn-BPDP demonstrates superior separation performance for C₃H₈/C₂H₆/CH₄ mixtures. Theoretical calculations further indicate that shape-matched aromatic surfaces provide enlarged contact interfaces with both C₃H₈ and C₂H₆ through multiple C─H···π interactions, thereby presenting an innovative approach for natural gas upgrading.