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Global energy demand is met in large part, by burning of fossil fuels, which is causing global warming. Mixed matrix membranes (MMMs) with metal organic frameworks (MOFs) as fillers are an interesting alternative for capturing post combustion CO2 which would make the energy sector sustainable. This research is focused on the synthesis of MOF ZIF‐94 from the recycling of its mother liquors and the incorporation of synthesized MOF into a Pebax MH 1657 for MMM fabrication. The pH and the temperature of ZIF‐94 synthesis are modified and monitored and this results in various nanoparticle diameters (average particle size in the range of 41 ± 8–180 ± 73 nm). Incorporation of ZIF‐94 significantly improves the performance of the bare Pebax MH 1657 membrane. The maximum CO2/N2 selectivity and CO2 permeability are obtained for 10 wt% ZIF‐94 loading in 9 wt% (polymer concentration in 70/30 (v/v) ethanol/water solution) Pebax MH 1657 matrix being 36 ± 7 (71% increment compared to bare membrane) and 137 ± 31 Barrer (80% improvement), respectively. [ABSTRACT FROM AUTHOR]

The solvent‐free encapsulation of caffeine and kojic acid was carried out in different carboxylate‐based MOFs [MIL‐53(Al), UiO‐66 and Mg‐MOF‐74] by high pressure (0.32 GPa) contact. This methodology enables fast and ecofriendly encapsulation and gives rise to additive@MOFs with physical and features equivalent to those of materials obtained by common liquid phase encapsulation processes. It could be applied to other host–guest systems, simplifying the procedures, reducing the use and waste of harmful chemicals, and approaching the conditions of interest in the industry. The characterization carried out by thermogravimetry, X‐ray diffraction, N2 adsorption, and 13C NMR provided information about the presence and conformation of the additives in the MOFs. The highest encapsulation values for caffeine (37 %) and kojic acid (32 %) were obtained with MIL‐53(Al). The solvent‐free encapsulation of caffeine and kojic acid is carried out in various carboxylate‐based MOFs, MIL‐53(Al), UiO‐66, and Mg‐MOF‐74, by high pressure (0.32 GPa) contact. [ABSTRACT FROM AUTHOR]

The use of thin film composites containing metal–organic frameworks (MOFs) as filler is of widespread interest for nanofiltration issues, since their thin selective layer allows a high permeation flow. The application of this kind of membranes for gas separation should provide a better permeance in comparison with other polymeric membranes and a reduction in the amount of MOF required for their fabrication. Here, the preparation of 50–100 nm thick polyamide flat membranes containing zeolitic imidazolate framework‐8 (ZIF‐8) nanoparticles is shown via interfacial polymerization, containing a lower amount of MOF (0.013 g m−2 membrane) as compared to other membranes used for gas separation. The membranes are applied for H2/CO2 separation at high temperatures and pressures, showing a stable performance at 180 °C for at least seven days. Outstanding separation values are 328 GPU of H2 and a H2/CO2 selectivity of 18.1 at 180 °C and 6 bar feed without transmembrane pressure. These membranes, also measurable without sweep gas, are highly suitable for industrial application. Polyamide flat membranes of 50 nm thickness and containing zeolitic imidazolate framework‐8 ZIF‐8 nanoparticles are prepared via interfacial polymerization. These membranes are applied for the H2/CO2 separation at high temperatures and pressures, showing outstanding values of 328 GPU of H2 and a H2/CO2 selectivity of 18, with a stable performance at 180 °C for at least seven days. [ABSTRACT FROM AUTHOR]