A stable metal-organic framework with well-matched pore cavity for efficient acetylene separation

Acetylene, an important petrochemical feedstock, is the starting chemical to produce many polymer products. Separating C₂H₂ from its by-product mixtures is still an energy-consuming process and remains challenging. Here, we present a metal-organic framework[Zn₂(bpy)(btec)], with a desirable pore geometry and stable framework, which demonstrated a high separation performance of C₂H₂ from simulated mixtures. With the desirable pore dimension and hydrogen bonding sites, Zn₂(bpy)(btec) shows by far the both highest C₂H₂/C₂H₄ and C₂H₂/CO₂ uptake ratios, very high adsorption selectivities and moderately C₂H₂ uptake of 93.5 cm³/cm³ under 298 K and 1 atm. Not only straightforwardly produced high purity of C2H4, but also recovered high purity of C₂H₂ (>98% in the regeneration process (>92% recovery). More notably, Zn₂(bpy)(btec) can be straightforwardly synthesized at a large scale under environmentally friendly conditions, and its good water/chemical stability, thermostability, and cyclic stability highlight the promise of this molecular sieving material for industrial C₂H₂ separation.