MOF‐on‐MOF Core–Shell Heterostructure With Synergistic Porous Interface for Highly Efficient Propane/Propylene Separation

Why It Matters

The breakthrough demonstrates that MOF heterostructures can achieve industrially relevant propylene/propane separation efficiency, potentially lowering energy consumption in petrochemical processing. It also provides a scalable design blueprint for other challenging gas separations.

Key Takeaways

• Core–shell MOF achieves 5.51 dynamic selectivity.
• Capacity reaches 1.14 mmol g⁻¹ at 298 K.
• Interface engineering overcomes capacity‑selectivity trade‑off.
• Ni‑MOF‑74 core provides high adsorption affinity.
• ZU‑609 shell enhances molecular sieving.

Pulse Analysis

The petrochemical sector processes millions of tonnes of propane‑propylene mixtures each year, yet separating the two C3 hydrocarbons remains energy‑intensive because of their similar physical properties. Conventional cryogenic distillation accounts for a large share of plant electricity use, prompting a search for adsorptive alternatives that can operate near ambient conditions. Metal‑organic frameworks have emerged as promising candidates thanks to tunable pore sizes and functionalizable metal sites, but most MOFs exhibit a trade‑off: materials with high uptake often sacrifice selectivity, and vice versa. Overcoming this limitation is critical for cost‑effective, low‑carbon separation technologies.

The Ni‑MOF‑74@ZU‑609 heterostructure tackles the trade‑off by pairing an adsorption‑rich Ni‑MOF‑74 core with a sieving‑oriented ZU‑609 shell. The core supplies abundant open metal sites that preferentially bind propylene, while the shell’s ultramicroporous channels impose size‑based discrimination against propane. 14 mmol g⁻¹ at 298 K and 1 bar—metrics that exceed those of the pristine components by a wide margin. The synergistic interface creates a cooperative environment where adsorption strength and molecular sieving reinforce each other, delivering unprecedented performance.

From a commercial perspective, such performance translates into reduced recycle streams, lower compression costs, and smaller equipment footprints for propylene recovery units. The core‑shell architecture is compatible with scalable synthesis routes, suggesting that pilot‑scale production could be feasible without extensive redesign of existing adsorption columns. Moreover, the interfacial engineering principle is transferable to other separations, including CO₂ capture, olefin/paraffin splits, and volatile organic compound removal. As the industry pushes toward greener processes, the Ni‑MOF‑74@ZU‑609 platform exemplifies how rational material design can bridge the gap between laboratory breakthroughs and real‑world deployment.