Liu Shanshan, Han Xue, Chai Yuchao, Wu Guangjun, Li Weiyao, Li Jiangnan, da Silva Ivan, Manuel Pascal, Cheng Yongqiang, Daemen Luke L, Ramirez-Cuesta Anibal J, Shi Wei, Guan Naijia, Yang Sihai, Li Landong
School of Materials Science and Engineering & National Institute for Advanced Materials, Nankai University, Tianjin, 300350, China.
Department of Chemistry, The University of Manchester, Manchester, M13 9PL, UK.
Angew Chem Int Ed Engl. 2021 Mar 15;60(12):6526-6532. doi: 10.1002/anie.202014680. Epub 2021 Feb 10.
The almost identical molecular sizes and volatilities of acetylene and carbon dioxide make their separation extremely challenging in industry. Reported here is the efficient separation of acetylene and carbon dioxide (v/v=2/1, which is relevant to that in the industrial cracking stream) in faujasite zeolites decorated with atomically-dispersed copper(II) sites under ambient conditions. In situ neutron powder diffraction and inelastic neutron scattering confirm that the confined copper(II) site displays chemoselective yet reversible binding to acetylene, whereas adsorbed carbon dioxide molecules are stabilized by weak host-guest supramolecular interactions with the framework oxygen centers, thus resulting in the efficient separation of these two gases under flow conditions. A designed adsorption-purging-desorption system based upon Cu@FAU is established for the recovery of high purity acetylene (98-99 %) from the mixture of acetylene and carbon dioxide, offering an unprecedented separation factor of 22.2 with an effective dynamic uptake of acetylene of 1.51 mmol g at 298 K.
乙炔和二氧化碳几乎相同的分子大小和挥发性使得它们在工业上的分离极具挑战性。本文报道了在室温条件下，原子分散的铜（II）位点修饰的八面沸石中乙炔和二氧化碳（体积比为2/1，与工业裂解气中的比例相关）的高效分离。原位中子粉末衍射和非弹性中子散射证实，受限的铜（II）位点对乙炔表现出化学选择性且可逆的结合，而吸附的二氧化碳分子则通过与骨架氧中心的弱主客体超分子相互作用而稳定，从而在流动条件下实现了这两种气体的高效分离。基于Cu@FAU建立了一种设计的吸附-吹扫-解吸系统，用于从乙炔和二氧化碳的混合物中回收高纯度乙炔（98-99%），在298K时提供了前所未有的22.2的分离因子，乙炔的有效动态吸附量为1.51 mmol g。
