Search

Metal-organic frameworks (MOFs) are a class of nanoporous materials. The development of efficient and environmentally friendly methods for activating MOFs is of great significance for its industrial application. In this work, nanoscale magnetic core-shell Cu-BTC@Fe 3 O 4 was prepared through a secondary growth strategy. The effects of different activation solvents (dichloromethane and ethanol, respectively) and temperatures on the surface area, pore structures and the adsorption of xylene isomers on Cu-BTC@Fe 3 O 4 were investigated. Ethanol as an activation solvent could more easily displace the precursors remaining in the channels of Cu-BTC@Fe 3 O 4 than dichloromethane, while the temperature change has no significant influence on the pore structure. The adsorption separation of xylene isomers on Cu-BTC@Fe 3 O 4 composite materials was studied using the batch vapor-phase adsorption, and liquid-phase breakthrough experiments. The activated Cu-BTC@Fe 3 O 4 (CH 2 Cl 2 -200 ​°C ​− ​C 2 H 5 OH) material has the highest adsorption capacity of 210.26 ​mg ​g−1 for p -xylene (p X). Cu-BTC@Fe 3 O 4 (C 2 H 5 OH) and Cu-BTC@Fe 3 O 4 materials have excellent adsorption capacity for m -xylene (m X), with the values of 200.19 ​mg ​g−1 and 219.63 ​mg ​g−1, respectively, which is about 4 times higher than that of Cu-BTC@Fe 3 O 4 (CH 2 Cl 2). The adsorption capacity sequence of xylene on Cu-BTC@Fe 3 O 4 (C 2 H 5 OH) and Cu-BTC@Fe 3 O 4 materials is m -xylene (m X) ​> ​ p -xylene (p X) ​> ​ o -xylene (o X), and that of other materials is p X ​> ​ m X ​> ​ o X. Nanoscale magnetic core-shell Cu-BTC@Fe 3 O 4 was prepared through a secondary growth strategy towards the adsorption separation of xylene isomers. [Display omitted] • Nanoscale magnetic core-shell Cu-BTC@Fe 3 O 4 was prepared through a secondary growth strategy. • The effects of different activation solvents and temperatures on the xylene isomers adsorption of Cu-BTC@Fe 3 O 4 were studied. • Using ethanol as an activation solvent could more easily displace the precursors remaining in the channels of Cu-BTC@Fe 3 O 4. [ABSTRACT FROM AUTHOR]

Two isomorphic metal-organic frameworks, [Co 2 (4-Ptz) 2 (BDC)(DMA)] n ( 1 ) and [Co 2 (4-Ptz) 2 (2-NH 2 -BDC)(DMA)] n ( 2 ) (4-Ptz=5-(4-Pyridyl)tetrazole, H 2 BDC=Terephthalic Acid, 2-NH 2 -H 2 BDC=2-Aminoterephthalic Acid, DMA=N,N-dimethylacetamide), have been successfully constructed through solvothermal reactions. Crystallographic data analysis reveals a binuclear Co(II) cluster-based structure for 1 and 2 , which were constructed by bridging two neighboring Co(II) ions with teterazole rings of 4-Ptz ligand together with one DMA oxygen atom. Simplifying Co 2 cluster as a 6-connecting node, complexes 1 and 2 reveal bcu-6 net. The CO 2 adsorption isotherms measurement at 273 K manifests higher adsorption quantities for 2 (33.8 cm 3 /g) than 1 (26.2 cm 3 /g), which was attributed to the introduction of NH 2 -group in 2 . [ABSTRACT FROM AUTHOR]

Abstract: Reactions of different metal salts with 3-pyridin-4-yl-benzoic acid (3,4-Hpybz) under ambient condition afford a series of 3-D metal-organic frameworks with two new types of (3,6)-connected net topologies. In the isomorphic complexes [M 2(μ-H2O)(3,4-pybz)4] n (M II=MnII for 1, ZnII for 2, or CdII for 3), the octahedral metal nodes are extended by the 3-connected pybz tectons to constitute 3-D arrays with the Schläfli symbol of (3.4.5)(32.44.55.62.72), whereas [Pb(3,4-pybz)2] n (4) shows a completely different 3-D (42.6)2(44.62.89) framework, which represents a subnet of the (4,8)-connected fluorite lattice. [Copyright &y& Elsevier]