Pore environment engineering in metal–organic frameworks for efficient ethane/ethylene separation. Issue 22 (21st May 2019)

• Record Type: Journal Article
• Authors: Wang, Xun; Niu, Zheng; Al-Enizi, Abdullah M.; Nafady, Ayman; Wu, Yufang; Aguila, Briana; Verma, Gaurav; Wojtas, Lukasz; Chen, Yu-Sheng; Li, Zhong; Ma, Shengqian
• Is Part Of: Journal of materials chemistry. Volume 7:Issue 22(2019)
• Page Start: 13585
• Page End: 13590
• Publication Date: 2019-05-21
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9ta02822f
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Methyl groups are introduced on the pore walls of a metal–organic framework to enhance the separation performance of C2 H6 /C2 H4 . Abstract : Selective adsorption of trace amounts of C2 H6 from bulk C2 H4 is a significantly important and extremely challenging task in industry, which requires an adsorbent with specific pore properties. Herein, we describe a strategy for adjusting the pore environment of metal–organic frameworks (MOFs) by introducing different amounts of methyl groups in the channel to enhance the guest–host interaction between C2 H6 and the framework. To prove this concept, 2, 3, 5, 6-tetramethylterephthalic acid (TMBDC) was deliberately added to a microporous MOF, Ni(BDC)(DABCO)0.5, affording a series of mixed-ligand materials, Ni(BDC)1− x (TMBDC) x (DABCO)0.5 ( x = 0, 0.2, 0.45, 0.71, 1), having different pore environments. Significantly, these mixed-ligand materials demonstrated improved performance in terms of the adsorption capacity of C2 H6 and C2 H4 with an unprecedented C2 H6 uptake of 2.21 mmol g −1 for Ni(TMBDC)(DABCO)0.5 at 0.0625 bar and 298 K. With the best theoretical C2 H6 /C2 H4 selectivity predicted by IAST, Ni(TMBDC)(DABCO)0.5 exhibited effective separation of C2 H6 /C2 H4 (1/15, v/v) and great recyclability in five consecutive adsorption/desorption cycles throughout the breakthrough experiment.