Synthesis of flower-like Co3O4-CeO2 composite oxide and its application to catalytic degradation of 1,2,4-trichlorobenzene

A micrometer-sized, nanostructured. flower-like Co3O4-CeO2 composite oxide was synthesized by an ethylene-glycol-mediated process. The composite oxide was an assembly of polycrystalline nanopartides, with a typical mesoporous structure. The composite's catalytic activity in 1,2,4-trichlorobenzene degradation was evaluated usinga pulsed-flow microreactor-gas chromatography system, and compared with that of quartz sand, commercial CeO2, commercial Co3O4, and a Co3O4/CeO2 equimass mixture. The composite oxide was a promising catalyst for 1,2,4-trichlorobenzene degradation. This is attributed to the structural features of the composite oxide with a high specific surface area and a high total pore volume, and the synergistic effect between the two composite phases. The easy creation of high-mobility active oxygen on CeO2 and the easy cleavage of Co-O bonds at the interface of the two components promote reactivity of Co3O4 in 1,2,4-trichlorobenzene degradation. Pulsed catalytic theory suggests a first-order reaction between the composite oxide and 1,2,4-trichlorobenzene, with an apparent activation energy of about 27 kJ/mol, and degradation on the Co3O4-CeO2 composite oxide would occur easily. (C) 2012 Elsevier B.V. All rights reserved.