Single-Step Ethylene Purification and MTO Product Separation in a Nitrogen-Rich Microporous Metal-Organic Framework.

The nitrogen-rich metal-organic framework (MOF) NTUniv-75, featuring a melamine (MA) functional group, enables efficient one-step C2H4 purification and methanol-to-olefins (MTO) product separation. At 298 K, its adsorption capacity follows the order C2H2 > C3H6 > C2H6 > C2H4. Breakthrough experiments showed that NTUniv-75 produced pure C2H4 from C2 mixtures with a productivity of 22.5 mL g-1. For MTO products, productivities reached 43.0 mL g-1 (C2H4) and 61.9 mL g-1 (C3H6). Notably, C3H6 addition nearly doubled the C2H4 yield. Modeling revealed that MA aids C2H2/C2H4 separation, while pocket-like apertures favor C2H6 adsorption. Additionally, C-H···π interactions between C2H6 and C3H6 enhance C2H4 yield.