Catalytic destruction of chlorobenzene over mesoporous ACeOx (A = Co, Cu, Fe, Mn, or Zr) composites prepared by inorganic metal precursor spontaneous precipitation

Abstract

Mesostructured ACeOx (A=Co, Cu, Fe, Mn, or Zr) composites with large specific surface area and developed mesoporosity were prepared by inorganic metal precursor spontaneous precipitation (IMSP) method. Influences of catalyst surface area, pore structure, reducibility, and active oxygen concentration on catalytic performance were studied. Both preparation route and metal precursor type affect metal active site dispersion, and the IMSP is a desirable approach for synthesis of metal composites with homogeneous active phase distribution. The original crystalline structure of CeO2 is well maintained although parts of transition metal cations are incorporated into its framework. The forming of An+–O2−–Ce4+ connections in ACeOx catalysts could reduce the redox potential of metal species, allowing effective redox cycles during oxidation reactions. CuCeOx demonstrates powerful catalytic efficiency with 99% of chlorobenzene (CB) destructed at 328°C, which is much lower than the other ACeOx oxides and Cu-doped catalysts synthesized via the incipient impregnation and coprecipitation methods (T99>405°C). The active site reducibility is the foremost activity determining factor for CB destruction.