A trapdoor chabazite zeolite for elevated-temperature adsorption separation of ethylene and ethane.

Elevated-temperature gas separation offers significant advantages, such as energy savings and the ability to directly integrate with hot process streams. Despite this, research on the critical adsorptive separation of ethylene/ethane (C2H4/C2H6) has predominantly been confined to room or near-ambient temperatures. Herein, we report the application of K+-exchanged chabazite (KCHA) zeolite for efficient elevated-temperature C2H4/C2H6 separation via a trapdoor mechanism. KCHA exhibits a high C2H4 uptake of 1.6 mmol/g at 1 bar and 423 K and demonstrates a remarkable selectivity of 14 for C2H4/C2H6 (50:50) mixtures. Computational studies reveal that the gas-cation interaction governs the thermal oscillation of the "door-keeping" cation. Dynamic breakthrough experiments further confirm the excellent elevated-temperature C2H4/C2H6 separation performance and its robust cyclic stability. This successful elevated-temperature separation not only demonstrates the potential of trapdoor-enabled zeolites but also provides guidance for the design and application of elevated-temperature C2H4/C2H6 separations.