(560fe) Catalytic Incineration of Volatile Organic Compounds on Pd/MnO2-CeO2 Catalysts

VOCs exhausts have high volatile, high diffusivity and are harmful for human body. How to destruct VOCs contamination is an important issue for environment protection. Catalytic oxidation is an effective way for treating the emissions of VOCs. The purpose of this study was to develop a catalyst which is active at low temperature and cost-effective. In this study, a series of Pd supported on MnO₂-CeO₂ were prepared. The samples were characterized by XRD, N₂-sorption, TEM, HRTEM, XPS, and H₂-TPR. The catalysts were tested for deep oxidation of toluene with GHSV of 10,000 h^-1. The XRD patterns showed only high crystallinity of CeO₂, no characteristic peaks for Pd and MnO₂ were observed, inferring that the particle size of palladium was less than 4 nm and the MnO₂ were in amorphous state. The TEM and HRTEM images confirmed that the average particle size of palladium was 2-4 nm and well dispersed on the support. Pd/MnO₂-CeO₂ showed very high activity.The presence of MnO₂ could increase the oxygen storage of CeO₂. Adding MnO₂ to Pd-CeO₂ catalysts created synergetic effect, resulting in high activity for complete oxidation of toluene.