Mineralization of reactive Black 5 in aqueous solution by ozone/H2O2 in the presence of a magnetic catalyst

Particles are often too small to be separated from a reaction system and recycled, especially in wastewater treatment via a catalytic ozonation process. Thus, the objective of this study was to prepare a magnetic catalyst (SiO2/Fe3O4) that can be recycled by using an external magnetic field. The effects of the characteristics of the magnetic catalyst, pH values, catalyst dosage, and initial concentration of Reactive Black 5 (RB5) on mineralization efficiency of the magnetic catalyst/H2O2/O-3 process were also investigated. The mineralization efficiency of RB5 under various conditions followed the sequence: SiO2/Fe3O4/H2O2/O-3 > SiO2/Fe3O4/O-3 > Fe3O4/O-3 approximate to H2O2/O-3 > O-3 > SiO2/Fe3O4/H2O2. Given the results of our reuse and recovery experiments, the magnetic catalyst shows considerable promise for use in water treatment. (C) 2009 Elsevier B.V. All rights reserved.