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Shi‐Qiang Wang Soumya Mukherjee Ewa Patyk‐Ka
mierczak Shaza Darwish Alankriti Bajpai Qing‐Yuan Yang Michael J. Zaworotko 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6702-6706
Purification of the C8 aromatics (xylenes and ethylbenzene) is particularly challenging because of their similar physical properties. It is also relevant because of their industrial utility. Physisorptive separation of C8 aromatics has long been suggested as an energy efficient solution but no physisorbent has yet combined high selectivity (>5) with high adsorption capacity (>50 wt %). Now a counterintuitive approach to the adsorptive separation of o‐xylene from other C8 aromatics involves the study of a known nonporous layered material, [Co(bipy)2(NCS)2]n ( sql‐1‐Co‐NCS ), which can reversibly switch to C8 aromatics loaded phases with different switching pressures and kinetics, manifesting benchmark o‐xylene selectivity (SOX/EB≈60) and high saturation capacity (>80 wt %). Structural insight into the observed selectivity and capacity is gained by analysis of the crystal structures of C8 aromatics loaded phases. 相似文献
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Kaushik Dey Shebeeb Kunjattu H. Anurag M. Chahande Prof. Dr. Rahul Banerjee 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(3):1177-1181
Covalent organic frameworks (COFs) have attracted attention due to their ordered pores leading to important industrial applications like storage and separation. Combined with their modular synthesis and pore engineering, COFs could become ideal candidates for nanoseparations. However, the fabrication of these microcrystalline powders as continuous, crack-free, robust films remains a challenge. Herein, we report a simple, slow annealing strategy to construct centimeter-scale COF films ( Tp-Azo and Tp-TTA ) with micrometer thickness. The as-synthesized films are porous (SABET=2033 m2 g−1 for Tp-Azo ) and chemically stable. These COFs have distinct size cut-offs (ca. 2.7 and ca. 1.6 nm for Tp-Azo and Tp-TTA , respectively), which allow the size-selective separation of gold nanoparticles. Unlike, other conventional membranes, the durable structure of the COF films allow for excellent recyclability (up to 4 consecutive cycles) and easy recovery of the gold nanoparticles from the solution. 相似文献
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Fereshteh Rashidi Johannes Leisen Seok‐Jhin Kim Ali A. Rownaghi Christopher W. Jones Sankar Nair 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(1):242-245
New membrane‐based molecular separation processes are an essential part of the strategy for sustainable chemical production. A large literature on “hybrid” or “mixed‐matrix” membranes exists, in which nanoparticles of a higher‐performance porous material are dispersed in a polymeric matrix to boost performance. We demonstrate that the hybrid membrane concept can be redefined to achieve much higher performance if the membrane matrix and the dispersed phase are both nanoporous crystalline materials, with no polymeric phase. As the first example of such a system, we find that surface‐treated nanoparticles of the zeolite MFI can be incorporated in situ during growth of a polycrystalline membrane of the MOF ZIF‐8. The resulting all‐nanoporous hybrid membrane shows propylene/propane separation characteristics that exceed known upper‐bound performance limits defined for polymers, nanoporous materials, and polymer‐based hybrid membranes. This serves as a starting point for a new generation of chemical separation membranes containing interconnected nanoporous crystalline phases. 相似文献
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Han Zhang Qiang Xiao Xianghai Guo Najun Li Prashant Kumar Neel Rangnekar Mi Young Jeon Shaeel Al‐Thabaiti Katabathini Narasimharao Sulaiman Nasir Basahel Berna Topuz Frank J. Onorato Christopher W. Macosko K. Andre Mkhoyan Michael Tsapatsis 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(25):7123-7123
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