Selective Ethane/Ethylene Separation in a Robust Microporous Hydrogen-Bonded Organic Framework
Selective Ethane/Ethylene Separation in a Robust Microporous Hydrogen-Bonded Organic Framework
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在坚固的微孔氢键有机框架中选择性分离乙烷/乙烯
DOI：
10.1021/jacs.9b12428
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发表时间：
2020
影响因子：
15
通讯作者：
Chen Banglin
中科院分区：
文献类型：
--
作者：
Zhang Xu;Li Libo;Wang Jia-Xin;Wen Hui-Min;Krishna Rajamani;Wu Hui;Zhou Wei;Chen Zhong-Ning;Li Bin;Qian Guodong;Chen Banglin
乙烷（C2 H6）与乙烯（C2 H4）的分离在用于工业制造的聚合物级C2 H4的生产中是最重要的。由于氢键的弱性质，在新兴的氢键有机框架（HOFs）中完全实现C2 H6/C2 H4的有效分离是非常具有挑战性的，并且仍然未被开发。本文报道了一种新型超硬霍夫吸附剂（称为霍夫-76 a）的基准实例，其Brunauer-Emmett-Teller表面积超过1100 m2 g-1，表现出C2 H6优先结合C2 H4，从而高度选择性地分离C2 H6/C2 H4。理论计算表明非极性表面和合适的三角形通道状孔在霍夫-76 a中的关键作用是与非平面C2 H6分子比与平面C2 H4更好地空间“匹配”，从而提供与C2 H6的整体更强的多点货车范德华相互作用。气体吸附等温线、理想吸附溶液理论计算、模拟穿透曲线和实验穿透曲线表明，霍夫-76 a对C2 H6/C2 H4的分离性能优异。在霍夫-76 a上的突破性实验表明，在第一个吸附循环中，可以从50/50（v/v）的C2 H6/C2 H4混合物直接生产聚合级乙烯气体，在298 K和1.01 bar下的高生产率分别为7.2 L/kg和18.8 L/kg。
The separation of ethane (C2H6) from ethylene (C2H4) is of prime importance in the production of polymer-grade C2H4for industrial manufacturing. It is very challenging and still remains unexploited to fully realize efficient C2H6/C2H4separation in the emerging hydrogen-bonded organic frameworks (HOFs) due to the weak nature of hydrogen bonds. We herein report the benchmark example of a novel ultrarobust HOF adsorbent (termed as HOF-76a) with a Brunauer–Emmett–Teller surface area exceeding 1100 m2g–1, exhibiting the preferential binding of C2H6over C2H4and thus highly selective separation of C2H6/C2H4. Theoretical calculations indicate the key role of the nonpolar surface and the suitable triangular channel-like pores in HOF-76a to sterically “match” better with the nonplanar C2H6molecule than the planar C2H4, thus affording overall stronger multipoint van der Waals interactions with C2H6. The exceptional separation performance of HOF-76a for C2H6/C2H4separation was clearly demonstrated by gas adsorption isotherms, ideal adsorbed solution theory calculations, and simulated and experimental breakthrough curves. Breakthrough experiments on HOF-76a reveal that polymer-grade ethylene gas can be straightforwardly produced from 50/50 (v/v) C2H6/C2H4mixtures during the first adsorption cycle with a high productivity of 7.2 L/kg at 298 K and 1.01 bar and 18.8 L/kg at 298 K and 5.0 bar, respectively.