Molybdenum containing cage like mesoporous KIT-5 for enhanced catalytic conversion of 1-butene and ethylene to propene

• Cage-like Mo-KIT-5 with various Si/Mo ratios was prepared.
• Mo-KIT-5 shows ordered mesoporous structure.
• The superior textural property leads to high dispersion of active Mo species.
• Mo-KIT-5 showed better activity than Mo/KIT-5 and Mo-SiO2.
• Mo-KIT-5 is advantageous over Mo-SBA-15 and Mo-KIT-6.

Molybdenum containing three-dimensional (3D) cage-like mesoporous KIT-5 (Mo-KIT-5) materials with various Si/Mo ratios was successfully prepared by one-pot hydrothermal synthesis. The obtained materials were characterized by various techniques, such as XRD, N2 physisorption, TEM, FTIR, UV-DRS, XPS, and NH3-TPD. Characterization results revealed that molybdenum species could be finely dispersed in the framework of KIT-5 without disturbing long-range ordering at Si/Mo ratios higher than 15, while collapse of mesoporous structure and presence of bulk MoO3 was observed for Mo-KIT-5-5 sample with a Si/Mo ratio of 5. Mo-contained materials were investigated in catalytic conversion of 1-butene and ethylene to propene. Among all of Mo-KIT-5 materials studied, Mo-KIT-5-40 with Si/Mo ratio of 40 exhibited best catalytic performance caused by the fact that it processed superior textural properties, substantial active Mo species, and appropriate amount of acidic sites. Further decreasing the Si/Mo ratio resulted in declined activity due to the presence of extraframework Mo species. It was found that doped Mo-KIT-5-40 showed better catalytic activity than control supported Mo/KIT-5-40 and Mo/SiO2-40 catalysts with same Mo loading due to the highly dispersed active Mo species on the mesoporous framework. Moreover, Mo-KIT-5 was also superior to other Mo containing mesoporous materials, such as Mo-SBA-15 with two-dimensional pores and Mo-KIT-6 with three-dimensional cylindrical pores, implying the advantage of this kind of ordered 3D cage-like mesoporous materials in this reaction.

3D cage-like mesoporous Mo-KIT-5 displayed superior catalytic performance to conventional supported catalysts and other mesoporous catalysts.Figure optionsDownload high-quality image (191 K)Download as PowerPoint slide