Reactivation of Fenton catalytic performance for Fe3O4 catalyst: Optimizing the cyclic performance by low voltage electric field

Abstract

Some Fenton Fe3O4 catalysts have the problem that the catalytic performance gradually weakens with increasing number of cycles, which brings economic losses and treatment difficulties to industrial wastewater treatment. In this work, the cyclic catalytic performance of Fenton N-rGO/Fe3O4 NPs catalysts for methylene blue (MB) has been enhanced by the reactivation process under the electric field. The effects of chemical reactions, voltage and electrolytic time on the cyclic performance of Fenton catalysts during the reactivation were discussed in detail. The first and fourth complete degradation of MB by fresh catalysts need 10 min and 20 min. After 2 h of reactivation using H2O as electrolyte at 1.0 V, the fourth complete degradation of MB only took 10 min. Zeta potential and CV curves showed that recovered catalyst has supplemented with surface electrons during the reactivation process. Characterizations demonstrated that the structure and composition of catalyst would not be influenced during the reactivation process. In short, the reactivation process under low voltage electric field is of great significance to Fenton Fe3O4 catalysts in the field of industrial water treatment.