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The separation of ethylene (C2H4) from a mixture of ethane (C2H6), ethylene (C2H4), and acetylene (C2H2) at normal temperature and pressure is a significant challenge. The sieving effect of pores is powerless due to the similar molecular size and kinetic diameter of these molecules. We report a new modification method based on a stable ftw topological Zr‐MOF platform (MOF‐525). Introduction of a cyclopentadiene cobalt functional group led to new ftw‐type MOFs materials (UPC‐612 and UPC‐613), which increase the host‐guest interaction and achieve efficient ethylene purification from the mixture of hydrocarbon gases. The high performance of UPC‐612 and UPC‐613 for C2H2/C2H4/C2H6 separation has been verified by gas sorption isotherms, density functional theory (DFT), and experimentally determined breakthrough curves. This work provides a one‐step separation of the ternary gas mixture and can further serve as a blueprint for the design and construction of function‐oriented porous structures for such applications. [ABSTRACT FROM AUTHOR]

The separation of ethylene (C2H4) from a mixture of ethane (C2H6), ethylene (C2H4), and acetylene (C2H2) at normal temperature and pressure is a significant challenge. The sieving effect of pores is powerless due to the similar molecular size and kinetic diameter of these molecules. We report a new modification method based on a stable ftw topological Zr‐MOF platform (MOF‐525). Introduction of a cyclopentadiene cobalt functional group led to new ftw‐type MOFs materials (UPC‐612 and UPC‐613), which increase the host‐guest interaction and achieve efficient ethylene purification from the mixture of hydrocarbon gases. The high performance of UPC‐612 and UPC‐613 for C2H2/C2H4/C2H6 separation has been verified by gas sorption isotherms, density functional theory (DFT), and experimentally determined breakthrough curves. This work provides a one‐step separation of the ternary gas mixture and can further serve as a blueprint for the design and construction of function‐oriented porous structures for such applications. [ABSTRACT FROM AUTHOR]

Ordered and flexible porous frameworks with solution processability are highly desirable to fabricate continuous and large‐scale membranes for the efficient gas separation. Herein, the first microporous hydrogen‐bonded organic framework (HOF) membrane has been fabricated by an optimized solution‐processing technique. The framework exhibits the superior stability because of the abundant hydrogen bonds and strong π–π interactions. Thanks to the flexible HOF structure, the membrane possesses the unprecedented pressure‐responsive H2/N2 separation performance. Furthermore, the scratched membrane can be healed by the treatment of solvent vapor, achieving the recovery of separation performance. [ABSTRACT FROM AUTHOR]

Ordered and flexible porous frameworks with solution processability are highly desirable to fabricate continuous and large‐scale membranes for the efficient gas separation. Herein, the first microporous hydrogen‐bonded organic framework (HOF) membrane has been fabricated by an optimized solution‐processing technique. The framework exhibits the superior stability because of the abundant hydrogen bonds and strong π–π interactions. Thanks to the flexible HOF structure, the membrane possesses the unprecedented pressure‐responsive H2/N2 separation performance. Furthermore, the scratched membrane can be healed by the treatment of solvent vapor, achieving the recovery of separation performance. [ABSTRACT FROM AUTHOR]

Carbon molecular sieve (CMS) membranes are ideal candidates for natural gas separation due to their rigid pore structures and stability. The chemical composite and spatial configuration of the used precursors for deriving CMS membranes can greatly influence the final microporous structure and separation performance of the membranes. Most CMS membranes are transformed from amorphous precursors such as polymers nowadays. Here, for the first time, we report a new type of CMS membrane derived from a crystalline porous hydrogen-bonded organic framework membrane (named HCMS). The conversion process has been studied with the characterization of TGA, FTIR, XRD, SEM, and pore size distribution. The effect of pyrolysis temperature on the membrane structure has been investigated to achieve optimized CO 2 /CH 4 separation performance. On the one hand, as the pyrolysis temperature increases from 550 to 650 °C, the pore size distribution of HCMS membrane is narrowed, which is conducive to improving the molecular sieving effect of the membrane. On the other hand, higher ratios of graphitic N and pyrrolic N, which show better affinity for CO 2 molecules than pyridinic N, are obtained on the HCMS membranes, leading to more favorable adsorption of CO 2. The optimized HCMS membrane pyrolyzed at 600 °C shows a remarkable CO 2 /CH 4 selectivity of 128 and excellent separation stability at varying temperatures and pressures. The HCMS membranes derived from the crystalline HOF precursor can also maintain a stable separation performance against physical aging. The results reported in this work may open the door to constructing CMS membranes with the precursor of crystalline porous membranes. Crystalline porous hydrogen-bonded organic framework membrane is employed as a new kind of precursor for the first time to derive carbon molecular sieve membrane with a narrow pore size distribution, which reveals good separation selectivity and stability for CO 2 /CH 4. [Display omitted] • For the first time, a HOF membrane is used as a precursor to derive HCMS membrane. • Ordered porosity of HOF leads to a narrow pore size distribution of HCMS membrane. • Effect of pyrolysis temperature on membrane structure and CO 2 affinity is studied. • The HCMS-600 membrane reveals the optimized CO 2 /CH 4 separation selectivity of 128. • The HCMS-600 membrane is long-term stable at variable temperatures and pressures. [ABSTRACT FROM AUTHOR]

Two lanthanide MOFs based on 3,3′-((2,3,6,7-tetramethoxyanthracene-9,10-diyl)bis(4,1-phenylene))diacrylic acid (H2LOMe), [Eu(LOMe)1.5(H2O)2]·3.5DMA·2H2O (1) and [Pr(LOMe)(H2O)4]·2.5DMA·3H2O (2) were synthesized under solvothermal conditions. Complex 1 displayed a 2D net with single nodal 44-sql topology, which further formed a 3D supramolecular architecture by strong π…π interaction. Complex 2 featured a 3D open framework with {42·84}-PtS topology. The PL spectrum results showed that 2 has potential application not only in the sensing of small organic molecules, such as DMF and NB, but also in detecting Al3+ and nitroaromatic derivatives. Furthermore, 2 also showed the selective adsorption of CO2 over CH4 and high catalytic activities with the cyanosilylation reaction. [ABSTRACT FROM AUTHOR]

Innentitelbild: Fabrication of a Hydrogen-Bonded Organic Framework Membrane through Solution Processing for Pressure-Regulated Gas Separation (Angew. B Geordnete und flexible b poröse Gerüste, die in Lösung verarbeitbar sind, sind wünschenswert, um kontinuierliche und großtechnische Membranen für die effiziente Gastrennung aufzubauen. In ihrer Zuschrift auf S. 3868 stellen D. Sun, Z. Kang und Mitarbeiter lösungsbasiert die erste Membran her, die aus einem Wasserstoffbrücken-gebundenen organischen Gerüst aufgebaut ist. [Extracted from the article]

Membranes with well-defined pore structure which have thin active layers may be promising materials for efficient gas separation. Graphene oxide (GO) materials have potential applications in the field of membrane separation. Here we describe a strategy for the construction of ultra-thin and flexible HKUST-1@GO intercalated membranes, where HKUST-1 is a copper-based metal–organic framework with coordinatively unsaturated metal sites, with simultaneous and synergistic modulation of permeance and selectivity to achieve high H2/CO2 separation. CuO nanosheets@GO membranes are fabricated layer-by-layer via repeated filtration cycles, then transformed to HKUST-1@GO membranes upon in situ reaction with linkers. The HKUST-1@GO membranes show enhanced performance for gas separation of H2/CO2 mixture. The number of filtration cycles is optimized to obtain H2 permeance of 5.77 × 10−7 mol m−2 s−1 Pa−1 and H2/CO2 selectivity of 73.2. Our work provides a facile strategy for the construction of membranes based on metal–organic frameworks and GO, which may be applied in the preparation of flexible membranes for gas separation applications. Graphene oxide membranes are promising materials for the separation of low molecular weight gases. Here, composite membranes comprising metal organic frameworks and graphene oxide show improved selectivity for the separation of hydrogen and carbon dioxide over graphene oxide alone. [ABSTRACT FROM AUTHOR]