Anchoring hydrogen bonding receptors into MOFs for enhancing simultaneous recovery of C2H4 and C3H6

Abstract

To obtain both C₂H₄ and C₃H₆ simultaneously in one adsorption–desorption cycle for complicated ternary C₂H₄/C₂H₆/C₃H₆ mixtures is important but difficult process in petrochemical industries. To address this challenge, an efficient strategy that anchoring hydrogen bonding receptors into MOFs has been successfully exerted, and a series of isostructural pillared porous MOFs have been developed for olefin purification. In particular, 1-Cl₂ can preferentially adsorb C₃H₆ and C₂H₆ rather than C₂H₄, and reveals high C₃H₆ uptake of 109.0 cm³ g⁻¹ even under low pressure of 20 kPa and 298 K. The breakthrough experiments of C₃H₆/C₂H₄ and C₂H₆/C₂H₄ binary mixtures as well as C₃H₆/C₂H₆/C₂H₄ ternary mixtures demonstrated that the 1-Cl₂ can more effectively yield high-purity C₂H₄ products (≥99.9 %) in one step and recover polymer-grade C₃H₆ (≥99.5 %) through a single adsorption–desorption cycle. GCMC simulation indicates multiple hydrogen bonds produced by plentiful Cl atoms in the channel is responsible for excellent olefin purification abilities of 1-Cl₂.