A Flexible Metal‐Organic Framework for the Removal of Propyne from Propylene

Abstract Efficient removal of propyne impurities from propylene is essential for producing high‐purity propylene. In this study, we utilize the flexible metal‐organic frameworks (MOFs) material, MOF‐508, for C 3 H 4 /C 3 H 6 separation. Propyne (C 3 H 4 ) induces a “Gate‐opening” effect in MOF‐508, transitioning it from a narrow‐pore phase to a large‐pore phase at low pressure. In contrast, propylene (C 3 H 6 ) only triggers this effect at a higher pressure of 0.55 bar. Notably, at 298 K and 0.5 bar, MOF‐508 adsorbs 71.9 cm 3 /g of C 3 H 4 , compared to just 7.9 cm 3 /g of C 3 H 6 . This selective adsorption significantly enhances C 3 H 4 /C 3 H 6 separation (50/50, v/v), as further demonstrated by dynamic breakthrough experiments.