Improving <scp>CH<sub>4</sub></scp> uptake and <scp>CH<sub>4</sub></scp>/<scp>N<sub>2</sub></scp> separation in pillar‐layered metal–organic frameworks using a regulating strategy of interlayer channels
Yang Chen, Yi Wang, Yong Wang, Qizhao Xiong, Jiangfeng Yang, Libo Li, Jinping Li, Bin Mu
Abstract
Abstract A pore engineering strategy involving the regulation of pillars in a series of pillar‐layered metal–organic frameworks was presented to promote pore size adjustment and pore environment optimization for efficient separation of CH 4 from coal‐mine methane. Compared with the original Ni(BTC)(BPY) and Ni(BTC)(TED), the suitable pore size and rich supply of carboxylate oxygens in the newly constructed Ni(BTC)(PIZ) resulted in the strongest recognition of CH 4 , leading to both high CH 4 uptake (1.62 mmol/g) and CH 4 /N 2 (50/50) selectivity (7.32) at 298 K and 1 bar. Its optimal balance performance between uptake and selectivity was better than most reported adsorbents, which further led to the most efficient separation of CH 4 from CH 4 /N 2 mixtures. The stability of the structure and performance was verified by repeated cycle tests. Overall, it is believed the structure constructed based on the regulation strategy of the interlayer channel would enable the application of promising metal–organic frameworks in industrial gas separation processes.