A Microporous Potassium-Organic Framework for Efficient C2H2/CO2 Separation

A novel potassium-based metal organic framework (TCBPA-K) was prepared by using a C-3-symmetric organic building block tris(4 '-carboxybiphenyl)amine (TCBPA). The compound has a rectangular like channel along the b axis and exhibits good selective adsorption performance. The single component gas adsorption isotherms indicated that the adsorption capacity of C2H2 is much higher than that of CO2 at 298 K and 1 bar. The isosteric adsorption enthalpies of TCBPA-K for C2H2 and CO2 are 30.6 kJ/mol and 9.1 kJ/mol respectively. Ideal adsorbed solution theory calculation recorded the separation selectivity of C2H2/CO2 (50/50, v/v) as 3.5.