A robust ethane-selective metal-organic framework with nonpolar pore surface for efficient C2H6/C2H4 separation

Abstract Due to similar physical and chemical properties, the separation of ethane (C2H6) and ethylene (C2H4) is an indispensable and extremely challenging task in petrochemical process. Although traditional C2H4-selective porous materials realize the separation of C2H6-C2H4 mixture, but subsequent multiple separation operations are required to produce high-purity C2H4. Herein, we designed a hydrophobic methyl group-modified metal-organic framework (MOF) for one-step efficient purification of C2H4 from C2H6-C2H4 mixture. The as-synthesized MOF constructed from inexpensive carboxylic acid and pyrazole mixed linkers shows high thermal stability and chemical stability (water resistance). Cooperative study on the pure-component sorption isotherm, Ideal Adsorbed Solution Theory method, adsorption heat calculation and grand canonical Monte Carlo (GCMC) simulation supports the unique C2H6-selective feature of the MOF. Breakthrough experiments revealed the one-step C2H4 purification from C2H6-C2H4 (1/1, 1/10 and 1/15) mixtures through the MOF around room temperature condition with nice recyclability.