The Co3O4 catalyst derived from ZIF-67 and their catalytic performance of toluene.

The reduction behaviour of Co 3 O 4 by H 2 -TPR. • The Co 3 O 4 catalysts were prepared by in-situ pyrolysis of ZIF-67. • The calcination temperature influences the structural properties of Co 3 O 4 catalysts. • The Co 3 O 4 -400 shows the highest removal the toluene performance. • The catalyst shows some resistance to the water vapor. A serial of Co 3 O 4 catalysts were prepared through a facile method of calcining of ZIF-67 at different temperatures. Physicochemical properties of the samples were characterized by the powder X-ray diffraction (XRD), thermogravimetric analysis-differential thermal analysis(TGA-DTA), scanning electron microscopy(SEM), the Brunauer-Emmett-Teller(BET) equation, H 2 temperature-programmed reduction (H 2 -TPR) and The X-ray photoelectron spectroscopy (XPS) techniques, and their catalytic performance were investigated for the oxidation of toluene. The structural characterization certified that the calcination temperature has an important effect to catalytic activities. With the increase of the calcination temperature, the BET surface area reduces, pore size increases and the ratio of Co3+/Co2+ and O ads /O latt firstly increase then decrease. The results showed that the conversion of toluene on the Co 3 O 4 -400 catalyst could reach 100 % when the reaction temperature was 240 ºC. The Co 3 O 4 -400 catalyst presented better performance and excellent resistance to H 2 O, which are very important to Industrial application. [ABSTRACT FROM AUTHOR]