Metal-Organic Framework with Polar Pore Surface Designed for Purification of Both Natural Gas and Ethylene

The advancement of high-value CH₄ purification technology within the natural gas industry is paramount for industrial processes. Herein, we constructed ZJNU-402, a new porous material characterized by permanent porosity, as an effective adsorbent for separating C₃H₈/CH₄ and C₂H₆/CH₄ mixtures. The findings reveal an outstanding C₃H₈ adsorption capacity of 68 cm³ g^-1 and a moderate C₂H₆ adsorption rate of 42 cm³ g^-1, with a notably lower CH₄ adsorption rate of 11 cm³ g^-1. Noteworthy is the exceptional selectivity of ZJNU-402 for C₃H₈/CH₄ and C₂H₆/CH₄, standing at 375 and 31, respectively, surpassing many previously documented high-performance adsorbents and breaking the traditional trade-off between adsorption capacity and separation selectivity. Adsorption heat calculations show that compared with CH₄ molecules, C₃H₈ and C₂H₆ molecules form stronger bonds with the skeleton, resulting in excellent separation performance. In addition, the breakthrough experiment of ZJNU-402 can also completely separate the ternary component C₃H₈/C₂H₆/CH₄ mixture to obtain 99.95 % high-purity methane. At the same time, ZJNU-402 also has excellent structural stability, excellent recyclability, and low isosteric adsorption heat. Consequently, ZJNU-402 exhibits substantial potential for augmenting the efficacy of natural gas enrichment processes.