Metal-organic frameworks for ethane-selective adsorption: A comprehensive review on structural design and separation applications

Abstract

Developing adsorption separation processes based on ethane-selective (C₂H₆-selective) adsorbents to replace energy-intensive cryogenic distillation is a promising alternative to purifying ethylene (C₂H₄), yet it remains challenging. The emergence of porous metal–organic frameworks (MOFs) has significantly advanced research on C₂H₆-selective adsorbents, enabling researchers to enhance C₂H₆-selective adsorption by accurately adjusting the pore size and surface chemical properties of these materials. Although extensive research in this field, the understanding of the structural recognition mechanisms is still insufficient, and further systematic studies are urgently needed to boost the selective adsorption performance of C₂H₆ and overcome the challenges posed by complex separation systems and industrial applications. This review is the first to systematically summarize the research advancements of C₂H₆-selective adsorbents during the past 15 years, and deeply explores their structural recognition mechanism, including flexible gate-opening, open-metal sites modification, pore surface regulation and confined pore space. In addition, the development from MOFs to other new porous materials and the application from two-component to multi-component separation system are summarized. Finally, this review offers a concise evaluation of the future development trends of C₂H₆-selective adsorbents and identifies the challenges that may arise in translating MOFs from academic research to practical industrial applications.