A microporous metal–organic framework with both open metal and Lewis basic pyridyl sites for highly selective C2H2/CH4and C2H2/CO2gas separation at room temperature

To immobilize both open metal and Lewis basic pyridyl sites into a microporous metal–organic framework, Cu6(PDC)6·2.6H2O (UTSA-50) was solvothermally synthesized and characterized. The combination of open metal sites and Lewis basic pyridyl functional sites leads to a high acetylene adsorption enthalpy of 39.4 kJ mol−1. As a result, UTSA-50 is a very promising MOF material for the highly selective separation of C2H2/CH4 and C2H2/CO2 at room temperature with the highest C2H2/CH4 separation selectivity of 68 ever reported and moderately high acetylene uptake of 91 cm−1 g−1.