Cobalt supported on mesostructured TiO2 catalysts has been prepared by a wet-impregnation method. The Co/TiO2 catalytic system showed better catalytic performance after support calcination at 380 °C. Co nanoparticles appeared well distributed along the mesopore channels of TiO2. After reduction pretreatment and reaction, a drastic structural change leads to mesopore structure collapse and the dispersion of the Co nanoparticles on the external surface. Along this complex process, Co species first form discrete nanoparticles inside the pore and then diffuse out as the pore collapses. Through this confinement, a strong metal-support interaction effect is hindered, and highly stable metal active sites lead to better performance for Fischer-Tropsch synthesis reaction toward C5+ products.

The hierarchical macro-mesoporous silica (MMS) was used for a first time as a support for catalysts for oxidation reactions. The macro-mesoporous silica was synthesized by the emulsions templating mechanism and modified separately or simultaneously using cobalt and manganese oxides. The obtained materials were characterized by different physicochemical methods and tested in the oxidation of CO and n-hexane combustion reactions. The modification of the MMS materials does not change significantly the mesopores characteristics; however, its pores are partially blocked by the oxides. For Co-MM sample agglomerates consisting of Co3O4 with average size of 100-150 nm and small spherical aggregates, encapsulated in the mesopores are formed. The amorphous manganese oxide preferentially fills up the mesopores in Mn-MM sample. Mixed oxide Co-Mn phases situated in the mesoporous network are formed in the bi-component Co-Mn samples. No significant change is observed either in the texture, or in the structural features of the catalysts after reaction. The highest catalytic activity for Co-MM sample in CO and n-hexane oxidation is related to the predomination of Co3+ species on the surface of Co3O4 and the more accessible oxide particles located outside the mesopores. The encapsulation of mixed Co-Mn oxides particles in the pores of the macro-mesoporous silica is responsible for a lower catalytic activity in comparison with that of the mono-component cobalt sample.

Here, mixed nanostructured ceria/zirconia oxides have been prepared either by wet impregnation on a nanostructured ZrO 2 or by co-condensation through an EISA-derived pathway. This latter method and the impregnation on amorphous ZrO 2 followed or not by a heating at 480°C lead to a uniform cerium distribution in the zirconia framework and solid solutions are formed. Stabilization of the tetragonal structure of nano ZrO 2 with the increase of the cerium content is observed by XRD and Raman spectroscopy. The surface Ce/Zr molar ratio determined by XPS is very closed to the bulk one, calculated from the X-ray fluorescence analysis. On the opposite, the appearance of nano sized ceria particles with the increase of the cerium content, a monoclinic/tetragonal mixture and an enrichment of the surface in cerium are noted if the impregnation is carried out on a nanostructured ZrO 2 previously calcined at 480°C. The obtained catalysts have been tested for the oxidation of toluene, used as a model volatile organic compound. The catalytic efficiency of the mixed oxides has also been compared to the one of a pure commercial ceria. Results show that the preparation method has a significant effect on the catalytic properties of the materials. Although pure ceria presents the best activity and selectivity, the nanostructured ZrO 2 previously calcined at 480°C and impregnated by 10 mol% of CeO 2 is almost as efficient as pure ceria.

Mono- and bi-component cobalt and manganese samples were prepared by "two-solvent'' technique using SBA15 as a support. The obtained materials were characterized by SAXS (Small angle X-Ray scattering), N-2 adsorption-desorption, X-ray diffraction, TEM (Transmission Electron Microscopy), X-ray photoelectron spectroscopy (XPS), TPR (Temperature-programmed reduction) and O-2-TPD (Oxygen Temperature-programmed desorption). The catalytic properties were tested in the complete oxidation of propane, n-hexane, and carbon monoxide. The modification of the SBA-15 materials with Co, Mn or simultaneously with both cobalt and manganese does not change significantly the mesoporous structure, however its pores are partially blocked by the oxides, resulting in the decrease in the specific surface area and in the pore volume. In the case of mono component Co-SBA-15, the clusters of Co3O4 are on the surface and they are partially located inside the pore system of SBA-15 while for Mn-SBA-15 sample, the oxide phases preferentially fill up the channels of SBA-15 forming nanowires. The mixed oxide nanowires are formed in the channels of CoMn-SBA-15 material along with small nanoparticles, aggregated outside of the channels. The mesoporous structure and morphology of SBA-15, type of oxide phases and the size of the oxide particles remain almost unchanged after tests in reaction of complete n-hexane oxidation and this is valid for all studied samples. The observed resistance towards agglomeration can be attributed to the mesoporous structure. On the other hand, after reaction the surface concentration of different cobalt and manganese species undergoes significant changes, except for the sample with equimolar Co:Mn ratio. The most active catalyst among bi-component Co-Mn samples in all studied reactions is the catalyst where the Co:Mn molar ratio is 1:0.5, which can be explained by the formation of finely divided oxides, thus ensuring highest reducibility and oxygen mobility.

TiO2 supported SBA-15 (xTi@SBA-15) materials with various high TiO2 loadings (x = 25, 50 and 70 wt%) have been used as support for impregnation of CoMo active phase for the hydrodesulfurization (HDS) of 4,6-di-methyldibenzothiophene (46DMDBT) as model molecule representative of gazole cuts. Compared to CoMoS supported over pure commercial TiO2 and conventional Al2O3, a higher total activity was measured corresponding to the presence of isomerization and dismutation reactions due to Bronsted acidity of TiO2. However, the HDS activity remains higher using alumina as support. Moreover, the DDS pathway was found favored to the HYD one with sulfided CoMo supported over xTi@SBA-15 catalysts contrary with alumina as support.

We describe a fast photocalcination process to prepare highly ordered silica mesoporous films through the use of a low-pressure amalgam arc (lambda: 185/254 nm). Because radiant power is 2-3 times higher than conventional low-pressure UV lamps, the elimination of the PEO-b-PPO-b-PEO copolymer template in the 2D hexagonal hybrid film has been completed within 50 min, without damage to the mesostructure. The degradation kinetics are impacted by film thickness and irradiance, but hardly copolymer concentration. Compared to thermocalcination, a narrower pore size distribution and lower energy consumption have been found. Photodegradation mostly originates from a photoablation mechanism induced by radiation at 185 nm, while oxidation due to photo generated reactive oxygen species plays a minor role. Photocalcination has been combined with an initial photoinduced mesostructuration (detailed in Part 1: Microporous Mesoporous Mater., 257 (2017) 42-50), resulting in an unprecedented "all UV" method to mesoporous silica films. The final process relies on dual wavelength photoactivation: UVB to form the hybrid copolymer/silica network, a flash intermediate thermal consolidation, and UVc to decompose the copolymer chains.

Introduction Grape marc waste generated from agro-industries have large deposit in the world (Food and Agriculture Organisation FAO, 2006; Celma et al., 2012). To minimize environment impact and to recycle such harmful residue, several recovery methods have been proposed. In particular, grape marc waste can be used as starting material for the production of added value products (i.e. alcohol, tartar, yeast, phenol compounds, oil, pharmaceuticals and cosmetics), as decontaminant for metal rich (copper and nickel) effluents, as feedstuff and organic fertilizer for soil. However, numerous applications have been abandoned due to the difficulty of grape marc to be biologically processed (high content of lignin and tannin) and for the high C/N ratio that is not adapted for soil amendment. A promising way for grape marc recovery is the chars production using pyrolysis technique. These chars that can be applied in different applications including adsorption for gas and water pollutants removal, hybrid composites formulation, ..... Grape marc, as all lignocellulosic biomass, consists mainly of cellulose, hemicellulose, and lignin and contains small amounts of minerals. These latter include significant amounts of alkaline and alkaline-earth species such as potassium, sodium, magnesium and calcium, which are essential nutrients of plants. Various studies have examined the effect of the inorganic elements on the pyrolysis process and reported many contradictory results on their catalytic effect (Khelfa, 2013; Hwang, 2015; Eom, 2012). In this context, the present investigation has been conducted with the aim to study the effect of minerals, and more specifically the role of potassium and magnesium species, on the pyrolysis process of grape marc as well as on the properties of chars which are key parameters for defining the suitable recovery process.

Designing sustainable and industrially viable processing methods to synthesize ordered mesoporous films is a necessary condition to tap their full potential of applications. In order to respond to this challenge, well-established photoacid-catalyzed sol-gel photopolymerization has been harnessed to prepare large (>100 cm(2)) and micrometer-thick porous silica films possessing a 2D hexagonal mesostructure. Our UV irradiation system consists of two inexpensive and low radiant power fluorescent UV tubes (3 mW cm(-2), 280-380 nm) enclosed in a hygrometric chamber. Precise conditions to promote copolymer/silica hybrid film mesostructuration have been determined as regards relative humidity, film thickness and templating agent concentration. The mesostructured films have been analyzed using an extensive range of techniques including electron microscopy, grazing-incidence small-angle X-ray scattering (GISAXS), and N-2 sorption measurements, and solid-state NMR spectroscopy. Mesoporous silica films with a specific surface area up to 314 m(2) g(-1) have been achieved with a very low level of microporosity. Coupling of X-ray diffraction (XRD) and FTIR spectroscopy has enabled to shed light into the photoinduced self-assembly mechanism. (C) 2017 Elsevier Inc. All rights reserved.

Using dual mesoporous titania as a support, due to the presence of intrinsic Brönsted acid sites, the main approach to 4,6-dimethylbenzothiophene (46DMDBT) hydrodesulfurization (HDS) becomes the direct desulfurization (DDS) route through isomerization and dismutation reactions, instead of the hydrogenation (HYD) pathway usually observed with a conventional promoted (by Ni or Co) MoS2/Al2O3 catalyst.

Zn-TiO2 mesoporous oxides have been prepared by the mechanical milling of zinc acetate either with a surfactant free mesoporous titania or with the hybrid mesophase, in that case the surfactant is still present inside the pores. After calcination in a muffle furnace or by induction, the obtained materials have been characterized in details by SAXS, XRD, EDX, nitrogen adsorption-desorption, XPS and UV spectroscopy. The photocatalytic activity of the mesoporous oxides has also been tested on the photo-degradation of methyl orange. The results show that the presence of surfactant favors the zinc dispersion, prevents from the formation of zincite and slows down the crystallization of anatase. The recovered materials present a mesopore arrangement with low crystallized walls. As a consequence, by comparison with the pure mesoporous titania having semi-crystalline anatase framework, their photocatalytic efficiency is decreased. By contrast, when zinc acetate is mechanically milled with the free surfactant mesoporous TiO2, agglomerated particles were observed by EDX and TEM and the zincite phase ZnO was detected by XRD. Studies of the Kubelka-Munk function revealed the presence of two band gap energies corresponding to 3.2 and 2.9 eV. The appearance of ZnO in the materials and the reduction of the band gap give a capacity for the photodegradation of methyl orange slightly higher than the one of the pure mesoporous titania with semi crystalline framework. (C) 2015 Elsevier B.V. All rights reserved.

Organoclays with thiol functionalities pending in the interlayer space were prepared by a single-template sol-gel synthesis. With magnesium nitrate, aluminum acetylacetonate, and mercaptopropyltrimethoxysilane involved, the reaction was established at room temperature. Characterizations were carried out using X-ray diffraction (XRD), X-ray fluorescence, IR, Raman, and solid-state Si-29 and C-13 NMR spectroscopies. XRD patterns exhibit broad peaks characteristics of badly organized solids. The comparison of the experimental basal distance with the theoretical one indicated that organic groups are not perpendicular to the sheets. IR spectra presented the structural bands of the framework while Raman spectroscopy was necessary to confirm the presence of the thiol function. The silicon NMR spectra showed that silanes were fully hydrolyzed but weakly condensated (presence of T1 sites). Comparison between magic-angle spinning (MAS) and cross-polarization MAS C-13 NMR spectra revealed rigid and mobile chains. To evaluate the retention capacity of these materials, tests on the chelating of heavy metal cations were performed. These hybrids offer a high retention capacity for mercury and copper (similar to 100%). On the basis of different characterizations, a retention mechanism is proposed.