摘要
The kinetics and Fenton-like mechanism are two challenging tasks for heterogeneous Fenton-like catalytic oxidation of organic pollutants. In this study, three kinetic models were used for the kinetic studies of Fe3O4/MWCNTs-H2O2 Fenton-like reaction for MO degradation. The results indicated that this reaction followed the first- order kinetic model. The relationship of reaction rate constant and temperature followed the Arrhenius equation. The activation energy and frequency factor of this system were calculated as 8.2 kJ.mo1-1 and 2.72 s-1, respectively. The quantifications of Fe ions dissolution and ,OH radicals generation confirmed that the homogeneous and hetero- geneous catalyses were involved in Fe3O4/MWCNTs＇H2O2 Fenton-like reaction. The reaction rate constant was closely related with Fe ions dissolution and ,OH radicals generation. Fe3O4/MWCNTs nanocomposites had typical ferromagnetic property and could be easily separated from solution by an external magnet after being used. Furthermore, Fe3O4/MWCNTs nanocomposites exhibited good stability and recyclability. Finally, the Fenton-like mechanisms on homogeneous and heterogeneous catalyses were described.
The kinetics and Fenton-like mechanism are two challenging tasks for heterogeneous Fenton-like catalytic oxidation of organic pollutants. In this study, three kinetic models were used for the kinetic studies of Fe3O4/MWCNTs-H2O2 Fenton-like reaction for MO degradation. The results indicated that this reaction followed the first- order kinetic model. The relationship of reaction rate constant and temperature followed the Arrhenius equation. The activation energy and frequency factor of this system were calculated as 8.2 kJ.mo1-1 and 2.72 s-1, respectively. The quantifications of Fe ions dissolution and ,OH radicals generation confirmed that the homogeneous and hetero- geneous catalyses were involved in Fe3O4/MWCNTs＇H2O2 Fenton-like reaction. The reaction rate constant was closely related with Fe ions dissolution and ,OH radicals generation. Fe3O4/MWCNTs nanocomposites had typical ferromagnetic property and could be easily separated from solution by an external magnet after being used. Furthermore, Fe3O4/MWCNTs nanocomposites exhibited good stability and recyclability. Finally, the Fenton-like mechanisms on homogeneous and heterogeneous catalyses were described.
基金
This work was financially supported by the Natural Science Foundation of Heilongjiang Province, China （Grant No. E2015065）.
