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Herein, the design of new catalysts obtained by the dispersion of the CoMoS active phase on mesostructured titania having different pore size and kind of porosity (monomodal vs. dual) for hydrodenitrogenation (HDN) of 1, 2, 3, 4‐tetrahydroquinoline (1234THQ) is reported. Obtained results show that with a selectivity around 93%, the hydrogenated pathway is by far the main route for 1234THQ hydrodenitrogenation. It is also demonstrated that the catalytic activities depend on the mesopore diameter: the larger the size of the mesopores is, the higher the HDN activity is. Comparing with the conventional CoMoP/Al2O3 catalyst, a slightly higher activity is obtained for the mesostructured TiO2‐based catalyst due to the promoter effect of titania. [ABSTRACT FROM AUTHOR]

The bulk Ni and Co boride alloys were synthesized using the typical reduction method with potassium borohydride in different Ni/(Ni + Co) ratios, 273 K and under an N2 atmosphere. These solids were characterized before the DBT HDS reaction using different techniques such as: X-ray diffraction (XRD), surface measurements (BET specific area, pore volume and pore diameter), chemical analysis, elemental analysis, differential calorimetry of scanning (DSC), X-ray photoelectron spectroscopy (XPS), temperature programmed reduction (TPR), and transmission electron microscopy (TEM); and after the reaction by XRD and chemical analysis. These bulk borides were tested as catalysts in the HDS reaction of DBT. Ni/(Ni + Co) ratios of 0.0 and 0.25 showed the highest catalytic activity. After that, the catalytic activity decreased and remained almost constant as the Ni content increased. XPS and XRD studies revealed that these metal borides partially decompose under reaction conditions to form sulfur species. Both phases, boride and sulfur compounds, are responsible for the catalytic activity. On the other hand, unlike classical supported hydrotreating catalysts, these boride alloys are more reactive towards the hydrogenation pathway in the DBT hydrodesulfurization (HYD) reaction, showing a similar behavior to noble metal-based catalysts, but with the advantage of being much cheaper and thio resistant. It is particularly interesting when the aromatic content in the diesel fractions must be reduced. Additionally, for the first time, the kinetic constants of the DBT hydrodesulfurization reaction using these Co and Ni alloys were established. [ABSTRACT FROM AUTHOR]

The successful preparation of organized porous inorganic fluorides (OPIFs) with a high specific surface area is demonstrated for MgF2. For the first time, macroporous MgF2 OPIFs with a surface area of above 200 m2 g–1 and mesoporous MgF2 powder were prepared through the assembly of preformed MgF2 nanoparticles and homemade polymer templates with a tunable size. These OPIF materials have been fully examined at different synthesis stages by means of powder X-ray diffraction, N2 sorption, scanning electron microscopy, and transmission electron microscopy analyses and 19F and 1H solid-state nuclear magnetic resonance. The relation between the nature, the size, and the amount of polymer template on the porous structure was deeply investigated. The MgF2 OPIFs present a higher thermal stability under air and F2 calcination than MgF2 nanoparticles as the structuration of the OPIF composite considerably slows down the crystallite growth during thermal treatment under air. OPIF materials were evaluated as heterogeneous catalysts for the fluorination of 2-chloropyridine under HF gas as a fluorinating agent at 350 °C. This study evidences catalytic sites with two Lewis acidity strengths (medium and low). [ABSTRACT FROM AUTHOR]

Liquid phase hydrodearomatization (HDA) of monoaromatic model molecules (toluene, indane, tetralin, cyclohexylbenzene, nonylbenzene) from naphtha and middle distillate was conducted at a temperature of 170 °C and a pressure of 100 bar over Ni/Al2O3 in order to compare their reactivity separately and in mixture. A reactivity scale was established where toluene is more reactive than tetralin, indane, cyclohexylbenzene and nonylbenzene. The difference of reactivity is due to steric hindrance of the substituent and its electronic effect. In all cases, the fully hydrogenated product is the main product. Toluene hydrodearomatization is inhibited by the presence of another monoaromatics. This inhibition effect is more significant with indane than with cyclohexylbenzene and nonylbenzene and tetralin corresponding to competitive adsorptions and highlighted by kinetic modeling.Graphical Abstract: [ABSTRACT FROM AUTHOR]