Salts as linker sources allow the preparation of high-quality carboxylate-based MOFs under unprecedented sustainable conditions: room temperature and water as the sole solvent.

Paradoxically, one of the most widely and successfully tested metal−organic framework (MOF)-based catalysts, i.e., the Fe-BTC material commercialized as Basolite F300, entails a certain "mystery": Its structure is unknown and only an indirect and complex preparation method has been reported. This work describes an easy preparation method of a Basolite F300-like material. Furthermore, this synthesis procedure is carried out under environmentally and economically sustainable conditions: at room temperature, in a few minutes and using water as the unique solvent. Several characterization techniques indicate that both commercial and lab-made Fe-BTC materials are very much similar in so many physicochemical properties. However, the herein reported Fe-BTC possesses better textural properties, especially regarding the external surface area. Both Fe-BTC materials catalyze the oxidation of cyclohexene with very similar selectivity. However, the sample prepared in the laboratory gives a notably higher conversion, which was attributed to its external surface area. Iron leaching, if any, was negligible, and no significant structural transformation was detected. Finally, this paper also gives valuable structural information about the semiamorphous Fe-BTC: it exclusively contains the smallest mesocages of MIL-100(Fe), which provides an important input for interpreting the role of these Fe-BTC materials in any application demanding high porosity.

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This work describes the preparation of mixed matrix membranes by casting from poly(1,4-phenylene ether−ether−sulfone) chloroform solutions containing dispersed zeolitic imidazolate frameworks. Diffusive studies of CO2 in the pristine poly(1,4-phenylene ether−ether−sulfone) membrane and composite membranes were performed at 6 bar and 298 K, using pulsed field gradient NMR techniques. The evolution of the heterogeneity of the diffusion environments as seen by NMR was monitored in terms of the diffusion time and a stretching parameter. The values of the self-diffusion coefficient increase with filler content, from 2.1 × 10−8 cm2 s−1 for pristine membranes to 9.3 × 10−8 cm2 s−1 for membranes with 30 wt % of filler. Sorption and permeation experiments carried out at different pressures were used to determine the dual-mode model parameters that describe the transport processes. Apparent diffusion coefficients of CO2 in the membranes were obtained from the time lag method, from parameters of the dual-mode model, and directly from the derivatives of the steady flux, expressed in terms of concentration and pressure, with respect to pressure. In general, the values of the apparent diffusion coefficients obtained by the three methods for pristine membranes are in rather good agreement with the self-diffusion coefficient obtained by the NMR technique. In composite membranes, the values of the self-diffusion coefficients are nearly 2 times those obtained using permeation and sorption experiments. The discrepancies between the values of the self-diffusion coefficients and the results obtained for the diffusion coefficient by other techniques are discussed. The filler contributes greatly to gas permeation by increasing the gas solubility in the composite membranes.

Summary: The synthesis of new N‐cyclopentyl‐exo,endo‐norbornene‐5,6‐dicarboximide (CpNDI) (3a) and N‐cyclohexyl‐exo,endo‐norbornene‐5,6‐dicarboximide (ChNDI) (3b) monomers was carried out. From these monomers, two polynorbornene dicarboximides with cyclopentyl and cyclohexyl pendant groups, poly(exo,endo‐N‐cyclopentyl norbornene‐5,6‐dicarboximide) (PCpNDI) and poly(exo,endo‐N‐cyclohexyl norbonene‐5,6‐dicarboximide) (PChNDI), respectively, were synthesized by ring opening metathesis polymerization (ROMP). PCpNDI, which bears a cyclic pentyl moiety, shows a higher Tg and mechanical properties compared to PChNDI. A comparison of density, fractional free volume, and gas permeability coefficients of the synthesized polynorbornenes shows that PCpNDI presents a slightly higher density and lower fractional free volume than PChNDI. It was also found that gas permeability coefficients for PCpNDI are lower than those of PChNDI. In all cases, the selectivity followed the usual trade‐off found in other glassy polymers: as gas permeability coefficients increase selectivity decreases.Poly(exo,endo‐N‐cyclopentyl norbornene‐5,6‐dicarboximide) (PCpNDI) was synthesized here by ROMP.magnified imagePoly(exo,endo‐N‐cyclopentyl norbornene‐5,6‐dicarboximide) (PCpNDI) was synthesized here by ROMP.