Synthesis, characterization and catalytic performance of well-ordered mesoporous Ni-MCM-41 with high nickel content

Abstract

The well-ordered Ni-MCM-41 with high nickel content was synthesized by a direct hydrothermal method using cetyltrimethylammonia bromide as the structure-directing agent in an ammonia aqueous solution. The resulting samples were characterized by X-ray diffraction, X-ray fluorescence spectroscopy, high-resolution transmission electron microscopy, nitrogen adsorption–desorption isotherms, H2 temperature-programmed reduction analyses, Fourier-transform infrared spectroscopy, ammonia temperature programmed desorption, and X-ray photoelectron spectroscopy. The results indicated that the material maintained ordered physical mesostructure of MCM-41 with high nickel content, and the nickel atoms were mainly in the framework with tetrahedral coordination. The materials possessed high specific surface area (800–580 m2 g−1), large total pore volume (1.05–1.22 cm3 g−1) and pore diameter (2.77–3.16 nm). The material exhibited excellent catalytic performance for the hydrocracking of coker wax oil, which was improved with the increasing of Ni content in the framework of the molecular sieves.