Preparation and Application of Fe-Cu/CA Electrode in Printing and Dyeing Wastewater Treatment

Iron-copper/carbon aerogel (Fe–Cu/CA) electrodes were prepared via N₂ carbonization and CO₂ high-temperature activation. Structural characterization indicated that CO₂ activation significantly increased the cathode’s porosity and specific surface area, enhancing the exposure of catalytic active sites. The CO₂-activated Fe–Cu/CA electrodes were used as cathodes in an electro-Fenton (EF) system for treating chemical oxygen demand (COD) and adsorbable organic halide (AOX) in actual printing and dyeing wastewater (PDW). The results showed effective COD removal over a wide pH range (3–8); under optimal conditions (pH = 3, current density 7 mA/cm 2 , aeration rate 0.5 L/min), the COD and AOX removal rates reached 73.0% and 65.5% respectively after 60 min, with a maximum H₂O₂ concentration of 32 mg/L. Fe and Cu served as efficient Fenton catalysts to promote COD degradation. Additionally, the cathode exhibited good catalytic stability, with COD removal rate slightly decreasing from 73.0% to 69.1% after five reuse cycles. This material provides a feasible approach for actual PDW treatment by EF process.