Highly selective adsorptive separation of olefin/paraffin through porous materials can produce high purity olefins in a much more energy-efficient way than the traditional cryogenic distillation. Here we report an ultramicroporous cobalt gallate metal–organic framework (Co-gallate) for the highly selective sieving separation of propylene/propane at ambient conditions. This material possesses optimal pore structure for the exact confinement of propylene molecules while excluding the slightly large propane molecules, as clearly demonstrated in the neutron diffraction crystal structure of Co-gallate⊃0.38C3D6. Its high separation performance has been confirmed by the gas sorption isotherms and column breakthrough experiments to produce the high purity of propylene (97.7%) with a high dynamic separation productivity of 36.4 cm3 cm–3 under ambient conditions. The gas adsorption measurement, pore size distribution, and crystallographic and modeling studies comprehensively support the high sieving C3H6/C3H8 separation in this MOF material. It is stable under different environments, providing its potential for the industrial propylene purification.

In comparison with the fast development of binary mixture separations, ternary mixture separations are significantly more difficult and have rarely been realized by a single material. Herein, a new strategy of tuning the gate‐opening pressure of flexible MOFs is developed to tackle such a challenge. As demonstrated by a flexible framework NTU‐65, the gate‐opening pressure of ethylene (C2H4), acetylene (C2H2), and carbon dioxide (CO2) can be regulated by temperature. Therefore, efficient sieving separation of this ternary mixture was realized. Under optimized temperature, NTU‐65 adsorbed a large amount of C2H2 and CO2 through gate‐opening and only negligible amount of C2H4. Breakthrough experiments demonstrated that this material can simultaneously capture C2H2 and CO2, yielding polymer‐grade (>99.99 %) C2H4 from single breakthrough separation.

A new approach for the synthesis of infinite Ti–O rod-based MOFs with superior photocatalytic H2 evolution performances was developed.

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