Performance of a Metal-Organic Framework MIL-53(Al)-Supported Cobalt Catalyst in the CO Catalytic Oxidation Reaction

A metal-organic framework (MOF) material MIL-53(Al) (MIL: Materials of Institut Lavoisier) with high thermal stability was prepared by the solvothermal method, and it served as a support material for a cobalt catalyst in the CO oxidation reaction. A comparison between the catalytic performance of the MIL-53(Al) and the Al2O3 support material was carried out to understand the catalytic behavior of the catalysts. The catalysts were characterized by thermogravimetric-differential scanning calorimeter (TG-DSC), Fourier-transform infrared (FTIR) spectroscopy, N2 adsorption-desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), and hydrogen temperature-programmed reduction (H2-TPR). The TG and N2 adsorption-desorption analyses showed that MIL-53(Al) had good stability and high surface area. XRD and TEM results indicated that the size of the Co3O4 nanoparticles (5.03 nm) supported on MIL-53(Al) was smaller than that (7.83 nm) on the Al2O3 support. The highly dispersed Co3O4 nanoparticles from the three-dimensional porous structure of MIL-53(Al) led to superior catalytic activity during CO oxidation. The H2-TPR spectra showed that the reduction in temperature of the Co/MIL-53(Al) catalyst was significantly lower than that of the Co/Al2O3 catalyst, implying a higher catalytic activity for the Co/MIL-53(Al) catalyst. Indeed, the heterogeneous catalytic composite material 715 Acta Phys. -Chim. Sin. 2014 Vol.30 Co/MIL-53(Al) catalyst exhibited much higher activity than the Co/Al2O3 catalyst in the CO oxidation test with 98% conversion at 160 °C and 100% conversion at 180 °C. The catalytic activity and structure of the Co/MIL53(Al) catalyst were stable during the reaction.