Fe2O3/diatomite materials as efficient photo-Fenton catalysts for ciprofloxacin removal

Preparation of Fe3O4@CSAC catalyst and its degradation performance and heat release mechanisms in sewage degradation

To investigate the exothermic characteristics of a heterogeneous Fenton system during the degradation of organic sewage and provide technical support for energy recovery in sewage treatment, the catalyst Fe3O4@CSAC (coconut shell-activated carbon) was prepared. Subsequently, both the degradation performance and exothermic behaviour of the (Fe3O4@CSAC)-H2O2 heterogeneous Fenton-like system in the degradation of sewage were studied. The results demonstrated that the (Fe3O4@CSAC)-H2O2 heterogeneous Fenton-like system exhibited a high degradation rate for sewage and released a significant amount of heat during the degradation process, making it suitable for energy recovery through a sewage-source heat pump. These findings showed that the concentration of added Fe3O4@CSAC and H2O2 significantly influenced the heat release in the reaction system, underscoring its potential for sustainable and adaptable applications in sewage treatment processes.

Heterogeneous Fenton treatment of shale gas fracturing flow-back wastewater by spherical Fe/Al2O3 catalyst

In this work, efficient Fenton strategy have been proposed for degradation of shale gas fracturing flow-back wastewater using the spherical Fe/Al2O3 supported catalyst. Prior to actual fracturing fluid treatment, the typical model wastewaters such as p-nitrophenol and polyacrylamide were employed to evaluate the catalytic properties of prepared catalyst, and then Fenton treatment of the shale gas fracturing flow-back wastewater was performed on the self-assembled catalytic degradation reactor for continuous flow purification. Results showed that under the conditions of 0.25 mol L-1 impregnating concentration, pH 4, 50 g L-1 catalyst and 0.75 mL L-1 30% H2O2, the removal efficiency of p-nitrophenol and polyacrylamide reached 74% and 61%, respectively, while the COD removal of fracturing flow-back fluid was approximately 48% with the residual 88 mg L-1 COD, meeting the emission standards of the integrated wastewater discharge standard (GB 8978-1996, COD < 100 mg L-1). This work offers new alternatives for Fenton treatment of real wastewater by efficient and low-cost supported catalysts.