(199a) High-Throughput Computational Screening of Metal-Organic Frameworks for Selective Adsorption of C2H6 over C2H4

C₂H₆/C₂H₄ separation is one of the most crucial processes in the petrochemical industry and currently practiced by energy-intensive distillation technology. As an alternative, adsorption-based separation is considered as technically feasible and economically viable, and there has been considerable interest to develop advanced adsorbents for C₂H₆/C₂H₄ separation. In this study, we computationally screen a large set (> 10000) of metal-organic frameworks (MOFs) to identify candidates for selective adsorption of C₂H₆ over C₂H₄. The quantitative relationships are established between adsorption performance metrics (C₂H₆ working capacity and C₂H₆/C₂H₄ selectivity) and structural descriptors (pore size and surface area), as well as isosteric heat. Top-performing 16 MOFs are identified with C₂H₆/C₂H₄ selectivity > 2.16 and C₂H₆ working capacity > 0.53 mol/kg, which are superior to the literature benchmarked MOF namely ZJU-120a. It is revealed that both pore size and pore shape are dominant factors to govern C₂H₆-selective adsorption. Moreover, the separation performance in MOF duplicates and geometrical analogues is elaborately analyzed and categorized. Finally, six strategies are proposed to boost C₂H₆/C₂H₄ separation by introducing catenation, aliphatic/aromatic linkers, pillar layers, framework flexibility, topological variants, and different metal nodes. These strategies provide bottom-up guidelines for the rational design of new MOFs for high-performance C₂H₆/C₂H₄ separation.