A fluorinated hydrophobic metal–organic framework for CH4 purification from seven-component C1/C2/C3 hydrocarbons mixture

• Created Ni-FDMOF with −CF 3 groups for enhanced pore environment. • Achieved ∼ 100 C3/CH 4 selectivity , surpassing standard MOFs . • Showed high moisture resistance , maintaining integrity in humidity. The efficient separation of light hydrocarbons from natural gas is crucial for natural gas purification, yet it remains a challenging and energy-intensive process. Adsorbent-based gas separation methods using metal–organic frameworks (MOFs) offer potential advantages, such as simplicity and energy efficiency. In this study, a pillar-layered MOF, Ni-FDMOF, was constructed by introducing trifluoromethyl (−CF 3 ) groups into the Ni-DMOF framework to modify the pore environment. The C2 and C3 recognition ability and hydrophobicity of Ni-FDMOF were investigated. Single-component adsorption tests and ideal adsorption solution theory (IAST) calculations confirmed that Ni-FDMOF exhibited higher selectivity for C2/CH 4 and C3/CH 4 separation than Ni-DMOF. Notably, Ni-FDMOF achieved an impressive C3/CH 4 selectivity of approximately 100, ranking among the top recorded MOFs . Theoretical calculations indicated that multiple attractive interactions between C2-C3 molecules and −CF 3 groups play a crucial role in enhancing the adsorption of C2-C3. Moisture stability experiments demonstrated that Ni-FDMOF is a robust MOF with low water vapor capacity, due to the presence of hydrophobic −CF 3 groups. Transient breakthrough simulations further verified the excellent separation of C1/C2/C3 seven-component mixtures by Ni-FDMOF, highlighting its potential for industrial applications.