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Meso/microporous composite material KIT-5/Beta (KB) with a cubic Fm3m mesoporous structure and BEA microporous structure was successfully synthesized by an in situ assembly method. And the corresponding NiW/KB catalysts were prepared for the hydrodenitrification (HDN) reactions of quinoline. The supports and catalysts were characterized using XRD, FTIR, N2-adsorption, TEM, SEM, pyridine-FTIR, XPS and HRTEM techniques. The results revealed that the textural and acidic properties of the composite materials were dramatically improved in comparison to those of pure silica KIT-5. NiW/KB-3 displayed the highest HDN activity (97.44%) among all the catalysts, which was attributed to the synergistic effects of the open channel structure, excellent textural properties, suitable acidity, the best sulfidation and dispersion of active species, implying that KB-3 has potential application in HDN reactions. Moreover, the quinoline HDN reaction networks of the NiW/KB-x series are proposed. [ABSTRACT FROM AUTHOR]

Pure KIT-5 and a series of Al-KT-X materials modified by different amounts of aluminum were synthesized by a direct hydrothermal method and acted as supports for the catalysts of a quinoline hydrodenitrification reaction with the NiW active phases supported. The results of X-ray diffraction (XRD), N2 isotherm absorption-desorption, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) for the supports indicated that Al species were embedded into the framework of the KIT-5 materials with a large pore size, pore volume, and specific surface area. The Pyridine-Fourier transform infrared spectroscopy (Py-IR) result of the catalysts demonstrated that the addition of aluminum atoms enhanced the acidity of the catalysts. The results of the high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectra (XPS) characterizations for the sulfide catalysts indicated that the embedded Al species could facilitate the dispersion of active metals and the formation of the active phases. Among all the catalysts, NiW/Al-KT-40 showed the maximal hydrodenitrogenation conversion (HDNC) due to its open three-dimensional pore structure, appropriate acidity, and good dispersion of active metals. [ABSTRACT FROM AUTHOR]