Direct Ethylene Purification from a Four-Component Gas Mixture by a Microporous MOF with Aromatic Pore Surface and Carboxylates

The single-step purification of ethylene (C₂H₄) from a mixture of carbon dioxide (CO₂), acetylene (C₂H₂), ethylene (C₂H₄), and ethane (C₂H₆) was achieved through MOF Compound-1, where the aromatic pore surface and carboxylates selectively recognized C₂H₆ and CO₂, respectively, resulting in a reversal of the adsorption orders for both gases (C₂H₆ > C₂H₄ and CO₂ > C₂H₄). Breakthrough testing verified that the C₂H₄ purification ability could be enhanced 2.6 times after adding impure CO₂. Grand Canonical Monte Carlo (GCMC) simulations demonstrate that there are interactions between CO₂ and C₂H₆ molecules as well as between CO₂ molecules themselves. These interactions contribute to the enhancement of the C₂H₄ purification ability upon the addition of CO₂ and the increased adsorption of CO₂.