In-situ heterogeneous electro-Fenton based on B, Fe-modified carbon felts for phosphorus nutrients treatment in dredged sediment

Abstract

A novelty in-situ heterogeneous electro-Fenton based on boron-modified and co-modified carbon felts (CF) such as B-CF, B, Fe-CF and B, Co-CF was employed for phosphorus nutrients treatment in dredged sediment. During which B, Fe-CF (1:1) was the optimal cathode for phosphorus nutrients and organic matter treatment with organic phosphorus (OP) and non-apatite inorganic phosphorus (Fe-P) conversion rates of 26.84% and 63.21%, respectively, since the generated H2O2 on bifunctional cathode could produce ·OH with material surface reduced Fe(II). Characterized by SEM, XRD and XPS, B and Fe were successfully loaded on the electrode with elemental percentages of 0.99% and 4.40%, while B2O3 and Fe2O3 were detected. The operating parameters like initial pH and current density were explored. B, Fe-CF had a high stability and outstanding catalytic capacity for 5 cycles of phosphorus nutrient treatment. The possible mechanism was also proposed based on the electron paramagnetic resonance (EPR) and radical quenching experiment, which demonstrated that ⋅OH and SO4·- mainly contributed to phosphorus nutrients treatment. In this work, a highly efficient and stable carbon material was successfully prepared to treat refractory pollutants in dredging sediment, which provides new ideas and methods for subsequent resource utilization.