A robust ethane-trapping metal-organic framework for efficient purification of ethylene

Owing to the similar physicochemical properties between ethane(CH) and ethylene(CH), obtaining polymerization-grade CH(≥99.95% pure) is still a tricky problem in the petrochemical industry. Here, we report a robust scandium-based metalorganic framework(Sc BPDC), which is connected by oxygen-rich phenyl ligand with exceptionally high thermal stability(up to873 K) and capacity of CH(4.94 mmol/g at 100 k Pa and 283 K), exhibiting superior separation performance of CH/CHmixture(the IAST selectivity is up to 1.7 at 283 K). Importantly, Sc BPDC can produce 8.96 L/kg CHwith ≥99.99% purity while the CH/CH(50:50, v/v) as the mixture injection and the low isosteric heat of Sc BPDC(16.4 k J/mol for CH) validates the facility of adsorbent regeneration. Furthermore, theoretical calculations demonstrate the CHmolecules are trapped in the nonpolar pore surface via C–H···π and C–H···O interactions between multiple hydrogen atoms of CHand the host framework.