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

Owing to the similar physicochemical properties between ethane (C₂H₆) and ethylene (C₂H₄), obtaining polymerization-grade C₂H₄ (≥99.95% pure) is still tricky problem in the petrochemical industry. Here, we report a robust scandium-based metal-organic framework (ScBPDC), which is connected by oxygen-rich phenyl ligand with exceptionally high thermal stability (up to 873 K) and capacity of C₂H₆ (4.94 mmol/g at 100 kPa and 283 K), exhibiting superior separation performance of C₂H₆/C₂H₄ mixture (the IAST selectivity is up to 1.7 at 283 K). Importantly, ScBPDC can produce 8.96 L/kg C₂H₄ with ≥99.99% purity while the C₂H₄/C₂H₆ (50:50, v/v) as the mixture injection and the low isosteric heat of ScBPDC (16.4 kJ/mol for C₂H₆) validates the facility of adsorbent regeneration. Furthermore, theoretical calculations demonstrate the C₂H₆ molecules are trapped in the nonpolar pore surface via C-H⋯π and C-H⋯O interactions between multiple hydrogen atoms of C₂H₆ and the host framework. [ABSTRACT FROM AUTHOR]