Synthesis, Characterization and Catalytic Performance of Well-Ordered Crystalline Heteroatom Mesoporous MCM-41

Mesoporous heteroatom molecular sieve MCM-41 bulk crystals with the crystalline phase were synthesized via a one-step hydrothermal method using an ionic complex as template. The ionic complex template was formed by interaction between cetyltrimethylammonium ions and metal complex ion [M(EDTA)]2− (M = Co or Ni)]. The materials were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, N2 adsorption-desorption isotherms, and X-ray absorption fine structure spectroscopy. The results showed that the materials possess a highly-ordered mesoporous structure with a crystalline phase and possess highly uniform ordered arrangement channels. The structure is in the vertical cross directions with a crystalline size of about 12 μm and high specific surface areas. The metal atoms were incorporated into the zeolite frameworks in the form of octahedral coordinate and have a uniform distribution in the materials. The amount of metal complexes formed by metal ion and EDTA is an essential factor for the formation of the vertical cross structure. Compared to Si-MCM-41, the samples exhibited better conversion and higher selectivity for cumene cracking.