The efficiency of algae removal of a novel Pt/Ti-Fe@Fe2O3/ACF/Ni electrochemical system with an iron-loaded activated carbon fiber (ACF)/nickel foam (Ni) composite cathode formed by loading Fe@Fe2O3 nanowires on ACF/Ni with chemical impregnation method and Ti-based platinum (Pt/Ti) anode was investigated without oxygen supply and under different iron loads and initial pH condition and compared with other electrochemical systems. And the corresponding reaction mechanism of Pt/Ti-Fe@Fe2O3/ACF/Ni neutral electrochemical system was studied based on the indirect measurement of ·OH, analysis of the concentration of iron ion and H2O2, pH value, and measurement of ·O2-. The algae removal efficiency of the novel electrochemical system could reach 92.3% under the condition of 0.03g FeCl3×6H2O addition at the preparation stage of the cathode, the initial algal concentration of 0.7×109~0.8×109cells/L, the current density of 75mA/cm2, and initial pH value of 6.2 after electrolyzed for 60min. In the Pt/Ti-Fe@Fe2O3/ACF/Ni electrochemical system, a large number of ·OH and ·O2- were produced around the Fe@Fe2O3/ACF/Ni cathode through the electrochemical reaction, which could make algal cells to break down and die. The primary mechanism of algae removal in this system could be the heterogeneous Electro-Fenton reaction.
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