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The effect of aromatic swelling agents on the pore geometry and pore size of mesoporous M41S materials is investigated, where benzene and 1,3,5-trisubstituted aromatic compounds are used as swelling agents. Benzene is incorporated and immobilized close to the surface of the micelle, whereas the more hydrophobic trisubstituted aromatic compounds are located in the hydrophobic core of the micelle, where they retain some mobility.

Environmental regulations concerning fuel‐related sulfur emissions are currently experiencing worldwide expansion. This is motivating the research and development of improved hydrotreating (HDT) catalysts with carefully engineered synthesis methods that maximize activity as ultimate goal. In this contribution, the effect of phosphorus doping and triethylene glycol (TEG) incorporation on the genesis of the CoMoS phase of model HDT catalysts is assessed. Following a surface‐science approach, α‐Al2O3 single crystals with four orientations: C(0001), A(112‾ 0), M(101‾ 0), and R(11‾ 02) are used as model supports of the traditional γ‐Al2O3 support for the study of active phase‐support interactions at the molecular scale. The model catalysts are prepared by traditional impregnation of a solution containing metal and phosphorus precursors and TEG. The catalysts are characterized in the sulfide phase by XPS, XAS, TEM, and AFM, revealing that the calcination step is key in the emergence of distinctive metal‐support interactions, which are directly related to the nature of alumina surface sorption sites. In addition, TEG incorporation on dried catalysts increases metal sulfidation and enhances promotion with respect to non‐additivated systems, especially at mild sulfidation temperatures. The catalytic activity of the model catalysts is tested in a thiophene hydrodesulfurization reaction, revealing the following activity trend with respect to alumina surface orientations: A112‾0 ≫ M101‾0 >R11‾02 , C(0001). This trend is identical to the one observed for non‐phosphorus doped non‐TEG additivated model systems, confirming the predominance of surface effects on the catalytic activity over those exerted by P and TEG. By transposing these results to the industrial γ‐Al2O3 support, the (100) facet would provide surface sites that lead to better performing catalysts. This could result in the development of novel supports, engineered to expose surface sites that maximize hydrotreating activity. [ABSTRACT FROM AUTHOR]

The utility of the flexible porous chromium terephthalate Cr(OH)([O.sub.2]C-[C.sub.6][H.sub.4]-C[O.sub.2]) denoted MIL-53(Cr) (MIL = Material from Institut Lavoisier) for the separation of mixtures of C[O.sub.2] and C[H.sub.4] and also the co-adsorption of C[O.sub.2] and C[H.sub.4] are studied. The results have shown that the coadsorption of C[O.sub.2] and C[H.sub.4] has led to a similar breathing of MIL-53(Cr) as with pure C[O.sub.2], where the breathing is controlled by the partial pressure of C[O.sub.2], but increasing the C[H.sub.4] content has decreased the transformation of large pore to narrow pore.

A study demonstrates that the contribution of a 3[d.sup.4] spin configuration to the valence electronic structure of Fe compounds can be probed via spin-selective Fe K-pre-edge absorption spectra, using resonant inelastic X-ray scatterings (RIXS). Findings suggest that the 3[d.sup.4] configuration of Fe(IV) can be unequivocally detected even in a mixture with the high-spin 3[d.sup.5] configuration of Fe(III).