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Densification process of MOF powders (HKUST-1, UiO-66, UiO-66-NH2, and UiO-67) into mechanically resistant pellets with maintained microporosity and enhanced volumetric uptake.

Organized macroporous-mesoporous alumina can be obtained via a dual-templating approach. Monodispersed polystyrene beads promote macropore formation, while a P123 surfactant templating agent drives the formation of ordered hexagonal mesopores throughout the alumina framework. These well-defined pore networks coexist over a wide range of temperatures and macropore sizes.

3 Shaping of metal-organic frameworks (MOFs) has become increasingly studied over the past few 4 years because it represents a major bottleneck toward their further applications at larger scale. 5 MOF-based macroscale solids should present similar performances to their powder counterparts along with adequate mechanical resistance. 3D printing is one of the promising technologies as it 7 allows the fast prototyping of materials at the macroscale; however, the large amounts of added 8 binders have a detrimental effect on the porous properties of the solids. Herein, a 3D printer was 9 modified to prepare a variety of MOF-based solids with controlled morphology from shear-10 thinning inks containing 2-hydroxyethyl cellulose. Four benchmark MOFs were tested for this 11 purpose: HKUST-1, CPL-1, ZIF-8 and UiO-66-NH 2. All solids are mechanically stable up to 0.6 12 MPa of uniaxial compression and highly porous with BET specific surface areas lowered by 0 to 13-25%. Furthermore, these solids were applied to high pressure hydrocarbon sorption (CH 4 , C 2 H 4 14 and C 2 H 6) and presented consequent methane gravimetric uptake (UiO-66-NH 2 , ZIF-8, and 15 HKUST-1) and highly preferential adsorption of ethylene of ethane (CPL-1).

We report herein the upscaled synthesis and shaping of UiO66-COOH for NH3 air purification. The synthesis of the zirconium-based MOF was carried out in a batch reactor in an aqueous suspension with a yield of 89% and a spacetime yield of 350 kg/day/m 3. Neither toxic chemicals nor organic solvents were used, allowing this MOF to be employed in individual or collective air purification devices. Freeze-granulation and extrusion shaping techniques were investigated. The NH3 air purification performances of UiO66-COOH in bead, tablet and extrudate forms were compared to those of commercial carbon based materials (type K adsorbents from3M and Norit). Testing conditions were chosen to reflect current standards for ammonia concentration (600-1200 ppm) and velocity. In addition, the breakthrough measurements were carried out at three different relative humidity levels (0%, 40% and 70%). Pellets and extrudates of UiO66-COOH outperformed commercial benchmark adsorbents in all conditions, especially in dry conditions, for which the commercial adsorbents suffered impaired ammonia uptake and shortened service life. Extrudates of UiO66-COOH also withstood attrition after intensive shaking.

Metal-organic frameworks represent a class of porous materials which developed considerably over the past few years. Their porous structure makes them outperforming conventional adsorbents in hot topics such as dihydrogen...

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MFI-type materials with a lamellar morphology were successfully synthesized by using mononitrogen surfactants specifically designed by molecular modelling. The mononitrogen surfactants directed the recrystallization of a crystalline layered polysilicate formed in situ, the magadiite, into a zeolite ZSM-5.Moreover, the surfactants allow the preservation of the lamellar shape of the magadiite and inhibit a further growth into one dimension, leading to the formation of zeolite ZSM-5 nanosheets with a thickness comprised between 2 and 3 nm and a Si/Al ratio of 24. This simple approach paves a new way for obtaining zeolite materials of controlled size and shape for specific catalytic applications.