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The Ni/SBA-15 and Ni/TiO2 catalysts with 20 wt% nickel with different metal–support interaction strength were designed using ordered mesoporous silica (SBA-15) and TiO2 (P25). The Ni/SBA-15 and Ni/TiO2 catalysts with 20 wt% nickel were investigated using various characterization techniques. It was found that the Ni/SBA-15 and Ni/TiO2 catalysts with 20 wt% nickel possess different nickel particle size and different reducibility because of the different strength between nickel and support interaction. Both Ni/SBA-15 and Ni/TiO2 catalysts were tested for the hydrodeoxygenation reaction of a model bio-oil using a fixed-bed reactor at different evaluation conditions. It was found that under high hydrogen pressure (≥7 bar), both Ni/SBA-15 and Ni/TiO2 catalysts are highly efficient because the organic oxygen compound could be converted completely. And the product selectivity is very sensitive to the hydrogen pressure. Under low hydrogen pressure (3–5 bar) Ni/TiO2 catalyst show rather higher selectivity toward aromatic hydrocarbon as compared with Ni/SBA-15 catalyst. Lower hydrogen pressure and reaction temperature will be beneficial to the aromatic hydrocarbon production. It is very important to reduction for the H2 consumption cost. TiO2 is a very potential candidate support for the catalyst design aiming to the sustainable aromatic hydrocarbon production.

Alpha-alumina (α-Al 2 O 3 ) materials has a wide range of applications because of its excellent properties at high temperature. Tabular α-Al 2 O 3 was unexpectedly synthesized by etching mullite from Si x Al y O z composites since our original intention was highly porous α-Al 2 O 3 . Silica-alumina xerogels with different Al/Si molar ratio as 3, 6, 9 and ∞ (pure alumina) were prepared via sol-gel route, followed by calcination at 1400 °C to obtain Si x Al y O z composites. XRD results showed that the composite existed as mullite when the Al/Si ratio equaled to 3 and as the combination of mullite and corundum (α-alumina) when the Al/Si ratio equaled to 6 and 9, while pure α-Al 2 O 3 was obtained when Al/Si ratio equaled to ∞ signed as sol-gel α-Al 2 O 3 . The mullite phase in Si x Al y O z composites could be etched completely by hydrofluoric acid under room temperature in terms of the treating time was long enough and left tabular α-Al 2 O 3 for the samples with Al/Si molar ratio as 6 and 9. The interaction between mullite and α-Al 2 O 3 during the thermo process may direct the formation of tabular morphology. Structural and property characterizations show the tabular morphology, low surface area, perfect crystallinity and weak acidity of α-Al 2 O 3 . Furthermore, the adsorption of dibenzothiophene, a molecular with planar morphology, on tabular α-Al 2 O 3 , sol-gel α-Al 2 O 3 as well as γ-Al 2 O 3 was investigated at room temperature in comparison. Tabular α-Al 2 O 3 exhibited the highest adsorption capacity and best regeneration ability than other two.

Activated carbons chemically treated by steam and concentrated H2SO4, were used as adsorbents for removing organic sulfur compounds from a model diesel. The modified activated carbon was characterized by N2 sorption, base titration and FTIR spectroscopy. As compared with the untreated activated carbon, the treatment by a steam at 900 °C increased the mesoporous volumes from 0.248 to 0.856 cm3/g and sulfur adsorption capacity for dibenzothiophene from 10.9 to 20.6 mg/g and the treatment by a concentrated H2SO4 at 250 °C increased the amount of surface acidic-oxygenated groups from 0.05 to 1.95 mmol/g, and total adsorption capacity for dibenzothiophene from 10.9 to 33.3 mg/g. The total adsorption capacity for dibenzothiophene is found to be proportional to the mesoporous volume and the amount of surface oxygen-containing groups. It is proposed that direct interaction between the sulfur atom and surface oxygen-containing groups plays an important role in the adsorption of organic sulfur compound.

The oxidation of 5-hydroxylmethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is a sustainable and promising method for the preparation of bio-derived aromatic polyesters. Nitrogen doped carbon material is an effective catalyst support in preparing supported nanoparticle metal catalysts in heterogeneous reactions. In this work, by pyrolysis of bio-waste carbon material, pomelo peel, under 800 °C flowing NH3, high nitrogen (up to 11.4 wt%) doped porous carbon material (NC) was facilely obtained. Pt nanoparticles (NPs) can be uniformly dispersed on NC surface and stabilized by the doped nitrogen dopant. Supported Pt NPs by NC-800 (Pt/NC-800) was proved to be an efficient catalyst in aerobic oxidation of HMF into FDCA. Control experiments show that the oxidation of 5-hydrox-ymethyl-2-furancarboxylic acid (HMFCA) to 5-formyl-2-furancarboxylic acid (FFCA) by supported Pt NPs was the key step to determine the oxidation rate of HMF to FDCA. With controlled experiment results and previous reports, a catalytic mechanism involving water, molecular O2, hydroxyl ions and Pt NPs was given and explained well of the phenomenon of high HMFCA concentration accumulation during reaction.

A series of high-performance catalysts based on nickel phosphide particles supported on SBA-15 have been synthesized by temperature-programed reduction of a nickel phosphate, previously impregnated in the mesostructured silica support. In these samples the loading of the active phase varied between 10% and 20% in a Ni basis, while nominal Ni/P ratios ranged from 0.5 to 3. The formation of different active phases, Ni2P, Ni12P5 or Ni3P, depending on the P/Ni proportion was verified by X-ray diffraction (XRD). The study of these catalysts by transmission electron microscopy (TEM) and Energy-Dispersive X-ray spectroscopy (EDX) revealed that the majority of the phosphide nanoparticles present a relatively uniform diameter evenly distributed within the SBA-15 channels. All the nickel phosphide catalysts, as well as a reference Ni/SBA-15 catalyst, were tested for the hydrodeoxygenation (HDO) of methyl oleate (C17H33–COO–CH3) in a high pressure continuous flow reactor. This compound was used as a convenient surrogate of triglyceride molecules present in vegetable oils, and following catalytic hydrotreating yields mainly n-alkanes at 30 bars and temperature in the 250–340 °C range. In all cases lower contact time and reaction temperature decrease the conversion but favor the formation of C18 alkanes, which is the preferred product in terms of carbon atom economy. In addition, this study reveals that activity and selectivity are affected remarkably by the Ni/P ratio. Maximum conversion is achieved for the catalysts prepared with an initial Ni/P ratio of 1, while selectivity to C18 is larger for the catalyst with an initial Ni/P ratio of 2. These catalysts contain predominantly the Ni2P phase, which seem to be the most active for this process, although the presence of Ni12P5 in the case of the catalysts with Ni/P = 2 appears to be also positive. On the basis of the product distribution it can be concluded that both hydrodeoxygenation and decarboxylation/decarbonylation reactions occur simultaneously over the nickel phosphide catalysts, whereas decarboxylation and cracking are the prevailing processes over the Ni/SBA-15 catalyst. Owing to these high yields of long-chain paraffins, SBA-15-supported nickel phosphide catalysts can be considered as a very promising catalyst for the transformation of vegetable oils into green diesel.