Yang Lingzhi, Yan Liting, Wang Ying, Liu Zhi, He Jiangxiu, Fu Qiuju, Liu Dandan, Gu Xin, Dai Pengcheng, Li Liangjun, Zhao Xuebo
State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, P. R. China.
Key Laboratory of Processing and Testing Technology of Glass & Functional Ceramics of Shandong Province, School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, P. R. China.
Angew Chem Int Ed Engl. 2021 Feb 23;60(9):4570-4574. doi: 10.1002/anie.202013965. Epub 2021 Jan 4.
The separation of acetylene and carbon dioxide is an essential but challenging process owing to the similar molecular sizes and physical properties of the two gas molecules. Notably, these molecules usually exhibit different orientations in the pore channel. We report an adsorption site selective occupation strategy by taking advantage of differences in orientation to sieve the C H from CO in a judiciously designed amine-functionalized metal-organic framework, termed CPL-1-NH . In this material, the incorporation of amino groups not only occupies the adsorption sites of CO molecules and shields the interaction of uncoordinated oxygen atom and CO molecules resulting in a negligible adsorption amount and a decrease in enthalpy of adsorption but also strengthened the binding affinity toward C H molecules. This material thus shows an extremely high amount of C H at low pressure and a remarkably high C H /CO IAST selectivity (119) at 1 bar and 298 K.
由于乙炔和二氧化碳这两种气体分子的尺寸和物理性质相似，因此它们的分离是一个重要但具有挑战性的过程。值得注意的是，这些分子在孔道中通常表现出不同的取向。我们报道了一种吸附位点选择性占据策略，利用取向差异在精心设计的胺功能化金属有机框架（称为CPL-1-NH₂）中从二氧化碳中筛分乙炔。在这种材料中，氨基的引入不仅占据了二氧化碳分子的吸附位点，屏蔽了未配位氧原子与二氧化碳分子之间的相互作用，导致吸附量可忽略不计且吸附焓降低，而且增强了对乙炔分子的结合亲和力。因此，这种材料在低压下显示出极高的乙炔吸附量，在1 bar和298 K下具有非常高的乙炔/二氧化碳IAST选择性（119）。
