title: [Degradation of 3,4- Dichlorobenzotrifluoride by Fe3O4/CeO2-H2O2 Heterogeneous Fenton-Like Systems].
abstract: The 3,4-Dichlorobenzotrifluoride (3,4-DCBTE) was dehalogenated with oxidation treatment by heterogeneous Fenton-like system, using nanoscale Fe304/CeO2 as a catalyst. This nanoscale catalyst was prepared by the impregnated method. As a highly active new heterogeneous Fenton-like catalyst, nanoscale Fe304/CeO2 not only has the characteristics of the traditional Fenton-like catalyst but also can prevent the secondary pollution which caused by Fe2+. To find the optimum catalytic conditions for nanoscale Fe3O4/CeO2, the influence factors were investigated. The results indicated that the degradation ratio of 3,4-DCBTE was significantly improved by adding nanoscale Fe3O4/CeO2, with the removal ratio reaching 97.76% in 120 minutes and 79.85% in 20 minutes. As the temperature increasing, the catalytic effect of nanoscale Fe3O4/CeO2 catalyst had been constantly improved obviously. As the pH decreased, the degradation ratio of 3,4-DCBTE increased. With the increase of dosage of hydrogen peroxide (H2O2), the degradation efficiency of 3,4-DCBTE initially increased and then decreased, because oxygen (O2) was generated in preferential self-reaction when an excess of (H2O2) was added. The optimum removal efficiency was observed with the dosage of 15 mg x L(-1). With the increased amount of catalyst, there was a same trend as dosage of hydrogen peroxide (H2O2). The degradation ratio of 3,4-DCBTE initially increased and then decreased, the optimum amount of catalyst was 0.5 g x L(-1). The results also suggested that the reaction process followed the first-order kinetics and the thermodynamic analysis demonstrated that the reaction was only needed low reaction activation energy.
authors.forename: Zheng-nan
authors.initials: ZN
authors.lastname: Sun
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.forename: Dong-li
authors.initials: DL
authors.lastname: Ji
authors.forename: Lin
authors.initials: L
authors.lastname: Zheng
mesh_terms: D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D005464:Fluorobenzenes / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007700:Kinetics; D010084:Oxidation-Reduction
chemical_list: D005464:Fluorobenzenes; D002563:Cerium; C030583:ceric oxide; D006861:Hydrogen Peroxide; D052203:Ferrosoferric Oxide