Efficient Purification of Ethylene from C2 Hydrocarbons with an C2H6/C2H2-Selective Metal–Organic Framework

The separation of ethylene (C 2 H 4 ) from C 2 hydrocarbons is considered as one of the most difficult and important processes in the petrochemical industry. Heat-driven cryogenic distillation is still widely used in the C 2 hydrocarbons separation realms, which is an energy intensive process and takes up immense space. In response to a greener, more energy-efficient sustainable development, we successfully synthesized a multifunction microporous Mg-based MOF [Mg 2 (TCPE)(μ 2 -OH 2 )(DMA) 2 ]·solvents ( NUM-9 ) with C 2 H 6 /C 2 H 2 selectivity based on a physical adsorption mechanism, and with outstanding stability; especially, it is stable up to 500 °C under an air atmosphere. NUM-9a (activated NUM-9 ) shows good performances in the separation of C 2 H 6 /C 2 H 2 from raw ethylene gases. In addition, its actual separation potential is also examined by IAST and dynamic column breakthrough experiments. GCMC calculation results indicate that the unique structure of NUM-9a is primarily conducive to the selective adsorption of C 2 H 6 and C 2 H 2 . More importantly, compared with C 2 H 4, NUM-9a prefers to selectively adsorb C 2 H 6 and C 2 H 2 simultaneously, which makes NUM-9a as a sorbent have the capacity to separate C 2 H 4 from C 2 hydrocarbon mixtures under mild conditions through a greener and energy-efficient separation strategy.