Abstract:
As volatile organic compounds (VOCs) are harmful to environment and human health, the purification of VOCs in the atmosphere has become more and more urgent. Among the various purification technologies for VOCs emission, catalytic combustion is considered to be the most effective one. Besides, cordierite ceramic carriers are widely used in industrial catalysis due to their high thermal stability and comparable hardness. Pseudo-boehmite, alumina modified by rare earths, and cerium-zirconium composite oxides were used as raw materials to prepare a slurry, in which alumina sol was acted as the binder. The optimum solid content of aluminum sol has been studied in previous studies. The emulsifier was used to obtain uniformly mixed slurry which was coated on a cordierite honeycomb ceramic carrier. CeZrO
x-Al
2O
3/Cordierite scaffolds were prepared by vacuum extraction method. The effects of pH value, the solid content of slurry, and the emulsifying time on the coating performance were investigated. When pH value of slurry is 3.62, the solid mass fraction of slurry is 38%, and the emulsifying time is 30 min, the washcoat showed the best coating performance with a high loading capacity of 127 g/L and a low mass loss of 0.2%. Then Pd/CeZrO
x-Al
2O
3/Cordierite monolithic catalysts were prepared by the incipient wetness impregnation method, and their catalytic performances for the catalytic combustion of propane were investigated. The catalysts were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Pd/CeZrO
x-Al
2O
3/Cordierite monolithic catalyst (Pd loading of 2.0 g/L) exhibited the best catalytic performance for the catalytic combustion of propane (
T50 of 318 °C and
T90 of 350 °C) among the studied catalysts, showing good industrial application prospects.