Insights into mechanism of catalytic ozonation of cinnamyl alcohol over core–shell Fe3O4@SiO2@La2O3 catalyst

Abstract

In this study, a magnetic Fe3O4@SiO2@La2O3 nano-catalyst with a core–shell structure was synthesized to improve the efficiency of catalytic ozonation of cinnamyl alcohol. The structure, morphology, and elemental composition of the catalyst were analyzed with the help of catalyst characterization methods. The mechanism of strengthened degradation efficiency and mineralization of cinnamyl alcohol in catalytic ozonation system in the existence of the catalyst were further discussed according to the analysis results. The results showed that the Fe3O4@SiO2@La2O3 catalyst can not only greatly improve the degradation of cinnamyl alcohol, but also has good reusability and stability. And its economic efficiency is relatively good. The degradation rate of cinnamyl alcohol could reach up to 99.8% at 30 min, and the COD could be removed by 28.5% at 60 min with the help of the catalyst. The degradation efficiency of cinnamyl alcohol by ozone oxidation alone was only 52.1% at 30 min, and the COD removal rate was only 24.2% at 60 min in the same experimental conditions. Besides, the possible degradation pathway and degradation mechanism of cinnamyl alcohol were proposed according to the intermediate products detected by gas chromatography-mass spectrometry.