A substituted imidazolate-based MOF (SIM-1) membrane has been crystallized in situ on a tubular asymmetric alumina support that can be exploited for gas separation through preferential adsorption.

The new square planar tetracarboxylate ligand L (4,4 0 ,4 00 ,4 000-(9,9 0-spirobi[fluorene]-2,2 0 ,7,7 0-tetrayl) tetrabenzoic acid) was synthesized and used for synthesis of the Metal-Organic Framework Cu 2 L (H 2 O) 2 $(EtOH) 4 denoted SBF-Cu. This material possesses the classical 4-4 regular tiling topology with paddle-wheel inorganic building units. Due to the presence of SBF cores, the interactions between the layers of this MOF confer it specific properties: high specific surface area, open metal sites under activation, and promising hydrogen uptake capacity.

The control of the atomic-scale properties of highly dispersed multimetallic particles represents a challenging question for the optimal use of metallic active centers in nanoscience. In particular, improving the formation of Pt x Sn alloyed clusters on γ-alumina of a size close to 1 nm with a high Sn0/Pt ratio represents a crucial step toward more selective heterogeneous catalysts. For that purpose, bimetallic SnPt-based and trimetallic SnPtIn-based catalysts were prepared by surface organostannic chemistry on monometallic Pt and bimetallic PtIn-based catalysts. These systems were characterized by a multitechnique approach combining CO chemisorption, temperature programmed reduction, scanning transmission electron microscopy, Mössbauer spectroscopy, and X-ray absorption spectroscopy. The nature of the PtSn phase in trimetallic SnPtIn-based catalysts is found to strongly depend on the way indium is initially introduced in the parent catalyst, by either wet impregnation or coprecipitation with aluminum precursor. The key role of In3+ species on the formation of PtSn alloyed clusters is revealed. By using density functional theory calculations, we give a rational interpretation of the experimental results and provide an atomic scale description of Pt x Sn y /γ-Al2O3 systems, with or without In3+ on the alumina surface. The formation of In–Pt, In–Sn, and O–Sn bonds is indeed favored when In3+ is present in the support. This work proposes an original approach for stabilizing Pt x Sn alloyed clusters with an elevated Sn0/Pt ratio and highly dispersed on γ-alumina using indium as “third element” introduced as In3+ on the support.

We report the supercell crystal structure of a ZIF-8 analog substituted imidazolate metal-organic framework (SIM-1) obtained by combining solid-state nuclear magnetic resonance and powder X-ray diffraction experiments with density functional theory calculations.

-Catalytic reforming process has been used to produce high octane gasoline since the 1940s. It would appear to be an old process that is well established and for which nothing new could be done. It is however not the case and constant improvements are proposed at IFP Energies nouvelles. With a global R&D approach using new concepts and forefront methodology, IFPEN is able to: -propose a patented new reactor concept, increasing capacity; -ensure efficiency and safety of mechanical design for reactor using modelization of the structure; -develop new catalysts to increase process performance due to a high comprehension of catalytic mechanism by using, an experimental and innovative analytical approach ( 119 Sn Mössbauer and X-ray absorption spectroscopies) and also a Density Functional Theory (DFT) calculations; -have efficient, reliable and adapted pilots to validate catalyst performance.Résumé -Le reformage catalytique : méthodologie et développement procédé pour une optimisation et une amélioration constante des performances -Le reformage catalytique est utilisé pour produire des essences à haut indice d'octane depuis les années 40. Il pourrait apparaître comme un « vieux » procédé mature et pour lequel aucune innovation n'est possible. Ce n'est pourtant pas le cas, et des améliorations permanentes y sont apportées par IFP Energies nouvelles. À l'aide d'une stratégie de recherche globale, IFPEN est en mesure de : -proposer un nouveau concept de réacteur breveté augmentant la capacité ; -assurer l'efficacité et la fiabilité des designs mécaniques des réacteurs via la modélisation fine des structures ; -développer des nouveaux catalyseurs augmentant les performances du procédé grâce à une compréhension poussée des mécanismes, ceci par le couplage d'expérimentation et de techniques analytiques innovantes ( 119 Sn Mössbauer et X-ray absorption spectroscopies) et aussi par modélisa-tion moléculaire quantique ; -proposer des évaluations fiables, précises et optimisées des catalyseurs sur une gamme d'unité pilote adaptée.

We report the supercell crystal structure of a ZIF-8 analog substituted imidazolate metal-organic framework (SIM-1) obtained by combining solid-state nuclear magnetic resonance and powder X-ray diffraction experiments with density functional theory calculations.

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We propose an original methodology to integrate local measurement for nontrivial object shape. The method employs the distance transform of the object and least-square fitting of numerically computed weighting functions extracted from it. The method is exemplified in the field of chemical engineering by calculating the global metal concentration in catalyst grains from uneven metal distribution profiles. Applying the methodology on synthetic profiles with the help of a very simple deposition model allows us to evaluate the accuracy of the method. For high symmetry objects such as an infinite cylinder, relative errors on global concentration are lower than 1% for well-resolved profiles. For a less symmetrical object, a tetralobe, the best estimator gives a relative error below 5% at the cost of increased measurement time. Applicability on a real case is demonstrated on an aged hydrodemetallation catalyst. Sampling of catalyst grains at the inlet and outlet of the reactor allowed conclusions concerning different reactivity for the trapped metals.