Synergistic Effects of Co 3 O 4 -CeO 2 Nanoparticles towards Catalytic Oxidation of Aromatic Hydrocarbons: A Study in Association with Carbon Monoxide and Humidity

[摘要] In this study, a series of Co 3 O 4 -CeO 2 nanocomposites with various Co 3 O 4 loading were fabricated by the impregnation method using cobalt(II) acetate as the cobalt precursor for the treatment of benzene, toluene, ethylbenzene, and xylene (BTEX). The as-prepared Co 3 O 4 -CeO 2 nanocomposites were thoroughly characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brumauer-Emmett-Teller (BET), hydrogen temperature-programmed reduction (H 2 -TPR), and temperature-programmed desorption (O 2 -TPD). The excellent reproduction of active oxygen species caused by the high dispersion of Co 3 O 4 crystals on the CeO 2 supports was established. In addition, the reduction peaks of Co 3 O 4 -CeO 2 nanocomposites were found at much lower temperatures compared to pure CeO 2 , considering their unique redox property influencing on the high catalytic activity. Among the characterized materials, the 5.0 wt.% Co 3 O 4 supported on CeO 2 (5.0Co–Ce) was the best system for catalytic oxidation of xylene, along with excellent performances in the cases of benzene, ethylbenzene, and toluene. Its catalytic activity increased in the order: . Furthermore, the addition of carbon monoxide (CO) as a coreactant permitted to improve the catalytic performances in such oxidations as well as the stability of as-prepared catalysts, even under humid conditions.

[学科分类] 泌尿医学