Decomplexation Performance of Cu–EDTA and Parameter Optimization by Three-Dimensional Electro-Fenton

Abstract

The strong stability of Cu–ethylenediaminetetraacetic acid (Cu–EDTA) results in the low decomplexation efficiency by the traditional Fenton process. For breaking this limitation, a three-dimensional electro-Fenton (3D-EF) system was constructed to study the decomplexation of Cu–EDTA at different pH, and the effects of Fe2+ concentration, particle electrode dosage, current density, and coexisting ions on decomplexation performance were investigated. The results showed that 3D-EF exhibited high pollutant removal efficiency in a wide pH range compared with the traditional electro-Fenton process. The optimal conditions for the removal of Cu–EDTA were as follows: the pH was 7, Fe2+ was 1 mmol L−1, granular activated carbon was 2 g L−1, and current density was 10 mA cm−2, and the optimum Cu–EDTA removal efficiency reached 90.95%. In addition, the presence of Cl− slightly improved the decomplexation efficiency, whereas NO3− and HPO42− inhibited the removal of Cu–EDTA. The kinetics of Cu–EDTA decomplexation in all experimental groups followed the first-order kinetic equation.

Recent progress in electrocatalytic selectivity in heterogeneous electro-Fenton processes

“…The 3D-EF reaction system using GAC particles as particle electrodes could effectively realize the decomplexation of Cu–EDTA, and the decomplexation efficiency could reach 90.95% at the initial pH of 7, 1 mmol L −1 Fe 2+ , 4 g L −1 GAC, and the current density of 10 mA cm −2 . 157 A novel combination of hetero-EF and electrocoagulation processes using a MOF-derived N–Co/Fe–PC composite as a cathode catalyst can be used to effectively remove the Cu–ciprofloxacin complex (Cu–CIP). The optimal removal efficiencies of Cu, CIP, and TOC were 99.69%, 96.40%, and 83.62%, respectively.…”