Separation of Xe and Kr is one of the greatest challenges in the gas industries owing to their close molecular structure and similar properties. Energy‐effective adsorption‐based separation using chemically stable carbon adsorbents is a promising technology. We propose a strategy for Xe/Kr separation using MOF‐derived metallic carbon adsorbents. M‐Gallate (M=Ni, Co) were used as precursors to fabricate CoNi alloy nanoparticles embedded carbon adsorbents by one‐step auto‐reduction pyrolysis. The optimal NiCo@C‐700 exhibits record‐high IAST selectivity (24.1) and Henry's selectivity (20.1) of Xe/Kr among reported carbon adsorbents. DFT calculations, local density of states calculation, charge density difference, and Bader charge analysis reveal the great affinity with Xe benefits from the presence of Ni or CoNi nanoparticles as a result of more charge transfer from Xe than Kr to metal, thus providing higher binding energy. Breakthrough experiments further verify NiCo@C‐700 a promising candidate for Xe/Kr separation.

The development of adsorption-based separation processes alternative to the energy-intensive cryogenic distillation for a mixture of propylene and propane remains essential but challenging in gas industries. Molecular sieving separation of C3H6/C3H8 on stable carbon adsorbents appeals to be promising, while it is quite challenging to realize due to the random distributions and arrangements of the internal pores in common carbons. Herein, a series of polysaccharide-based CD-MOF-derived ultramicroporous carbon adsorbents with their pore size tuned at a subangstrom level were prepared. Molecular sieving separation of C3H6/C3H8 was realized on the optimal C-CDMOF-2-700 owing to the delicate structure with an appropriate pore size (5.0 Å). Besides, C-CDMOF-2-700 exhibited a high C3H6 uptake of 1.97 mmol g–1 under ambient conditions. An ultrahigh uptake ratio of C3H6/C3H8 at 1.0 kPa (403) was also achieved, outperforming all reported adsorbents. Kinetic adsorption tests and breakthrough experiments further demonstrate this well-designed carbon adsorbent to be promising in industrial C3H6/C3H8 separation.

Separation of Xe and Kr is one of the greatest challenges in the gas industries owing to their close molecular structure and similar properties. Energy‐effective adsorption‐based separation using chemically stable carbon adsorbents is a promising technology. We propose a strategy for Xe/Kr separation using MOF‐derived metallic carbon adsorbents. M‐Gallate (M=Ni, Co) were used as precursors to fabricate CoNi alloy nanoparticles embedded carbon adsorbents by one‐step auto‐reduction pyrolysis. The optimal NiCo@C‐700 exhibits record‐high IAST selectivity (24.1) and Henry's selectivity (20.1) of Xe/Kr among reported carbon adsorbents. DFT calculations, local density of states calculation, charge density difference, and Bader charge analysis reveal the great affinity with Xe benefits from the presence of Ni or CoNi nanoparticles as a result of more charge transfer from Xe than Kr to metal, thus providing higher binding energy. Breakthrough experiments further verify NiCo@C‐700 a promising candidate for Xe/Kr separation.