Effect of coke formation on catalytic activity tests for catalytic combustion of toluene: the difficulty of measuring TOF and T98 accurately

Silicotungstic acid modified CeO2 catalyst with high stability for the catalytic combustion of chlorobenzene

The catalysts' redox capacity and surface acidity was important during the catalytic combustion of chlorobenzene (CB). CeO₂ showed great attractiveness due to its high oxygen storage capacity. Furthermore, the increase of acidity on the catalyst surface could improve the resistance to the chlorine poisoning. In this work, the silicotungstic (HSiW) modified CeO₂ catalysts prepared by four cerium salts and exhibited the different morphologies and catalytic activity. The HSiW modified CeO₂ catalyst prepared by Ce(CH₃COO)₃ (Cat-A) exhibited the best catalytic activity due to its abundant surface weak acid sites, more Ce³⁺ species and surface adsorption oxygen. The HSiW mainly located on the CeO₂ (111) planes of the Cat-A, which was conducive to redox property of CeO₂, thus promoting the deep oxidation of CB. Meanwhile the redox ability together with the weak acidity influenced the catalytic efficiency at low temperature. And the redox ability played a major role at high temperature. In addition, the Cat-A still possessed high stability and water resistance and maintained high activity after continuous catalytic oxidation of CB at 235 and 295 °C for 100h, exhibiting the possibility of industrial application.