Efficient Removal of Toxic Pollutants Over Fe-Co/ZrO Bimetallic Catalyst with Ozone.

Fe-Co bimetallic oxides supported on mesoporous zirconia (Fe-Co/ZrO) was prepared using incipient wetness co-impregnation method and characterized by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and UV-vis diffuse reflectance spectra. Compared with individual component Fe or Co catalysts, Fe-Co/ZrO exhibited higher ozonation efficiency for the degradation of the tested toxic pollutants, as demonstrated with the herbicides 2,4-dichlorophenoxyacetic acid and pharmaceutical phenazone, diphenhydramine hydrochloride in aqueous solution. Furthermore, the characterization studies indicated that Fe-Co oxides were highly dispersed on the surface of mesoporous zirconia with multivalent oxidation states. The interfacial electron transfer process was greatly enhanced due to the presence of two redox couples (Fe/Fe and Co/Co) in Fe-Co/ZrO, which caused the higher catalytic reactivity for ozone decomposition into OH radicals, leading to the efficient removal of toxic pollutants in aqueous solution. The catalytic mechanism of pollutants degradation over Fe-Co/ZrO with ozone was proposed on the basis of all information obtained under different experimental conditions. Graphical Abstract: The multivalent oxidation states, high dispersion and the synergistic effect of Fe-Co oxides in Fe-Co/ZrO enhanced the interfacial electron transfer process, which caused the higher catalytic reactivity for the degradation of toxic pollutants in aqueous solution.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]