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Abstract: Supported nickel catalysts for aqueous-phase catalytic hydrogenation/dehydration of furfural were prepared using impregnation method with different supporting materials. Effects of supporting materials, nickel loading and reaction temperature on conversion rate of furfural as well as selectivity for desired product C5 were systematically studied. Experiments showed that catalytic activity of Ni/SiO2–Al2O3 was obviously higher than that of Ni/γ-Al2O3. The conversion of furfural over 14wt.%Ni/SiO2–Al2O3 catalyst was 62.99% under the temperature of 140°C and the cold pressure of H2 3.0MPa, while that was 19.19% over 14wt.%Ni/γ-Al2O3 under the same conditions. Conversion rate of furfural increased with temperature, but selectivity for desired product decreased with temperature. Tentative reaction mechanisms of hydrogenation/dehydration were proposed. In order to investigate catalyst recyclability, a batch of Ni/SiO2–Al2O3 was reused three times and analyzed by Thermogravimetry (TG). It was found that considerable amount of coke formed on Ni/SiO2–Al2O3 surface and deteriorated its activity dramatically after second use. [Copyright &y& Elsevier]

The preparation of green and economical bio-aviation fuel is a priority for the sustainable development industry. In this study, Jatropha oil was used as a raw material to catalyze the conversion of raw material to aviation kerosene fraction by photothermal coupling under the conditions of light and low temperature. The correlations among conversion rate, target alkane selectivity, composition distribution, and catalyst microstructure were investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), nitrogen (N2) adsorption and desorption, X-ray fluorescence (XRF), ammoniatemperature programmed desorption (NH3-TPD), ultraviolet-visible spectrophotometry (UV-Vis), and other characterization. The correlation between conversion and target alkane selectivity and composition distribution and catalyst microstructure was investigated, and different modification methods and different molecular sieve materials were selected. The results showed that the molecular sieves modified with the solid dispersion method could retain the structural stability of titanium dioxide (TiO2) and molecular sieves to a great extent while slightly enhancing the pore capacity and pore size of the catalyst to make it easier to adsorb reactants; the introduction of active metal platinum (Pt) could reduce the forbidden bandwidth of the catalyst, increase the weak acid amount of the catalyst, improve the adsorption capacity of hydrogen (H2), and thus improve the catalytic ability, resulting in a suitable catalyst for this study: P-21. The photothermal catalytic reaction of Jatropha oil using P-21 catalyst obtained 97.21% conversion and 74.99% selectivity of the target alkanes under the optimal process parameters. The results of this study provide effective catalyst parameters for research in the field of clean energy. [ABSTRACT FROM AUTHOR]