Three-dimensional electro-Fenton degradation of Rhodamine B with efficient Fe-Cu/kaolin particle electrodes: Electrodes optimization, kinetics, influencing factors and mechanism

Optimization of the 3D electro‐Fenton process in removal of acid orange 10 from aqueous solutions by response surface methodology

“…This may be due to the formation of a parasitic electrochemical reaction such as reducing oxygen to water instead of H 2 O 2 on graphite [Eqn (6)] and oxidizing the water to oxygen instead of •OH on Ti/PbO 2 [Eqn (7)]. Similar results were reported by Zhang et al for degradation of rhodamine B using the electro‐Fenton process combined with Kaolin/Fe‐Cu . The effect of the NF‐Fe particle electrode on dye removal efficiency is shown in Fig…”

“…During the application of the appropriate voltage in the electro‐Fenton process, the particles are polarized in the form of microelectrodes that can not only reduce the distance between the electrode and the pollutant, but also provide active sites for absorbing the contaminants and for increasing the mass transfer. In addition, the particles as a third electrode can increase catalytic reactions, such as electrochemical reduction of O 2 to H 2 O 2 and its degradation into •OH by direct decomposition and loading of Fe 2+ onto the particle surface …”

“…In recent years, researchers have suggested the use of activated carbon, kaolin, nickel foam, bentonite and carbon nanotubes as the supporting material and particle electrode. Amongst these, nickel foam has shown unique properties such as high conductivity, high porosity, high specific surface area and resistance to corrosion giving enhanced mechanical durability and catalytic activity, leading to its use in various fields as catalyst, ion exchanger and supporting material …”

“…In addition, the particles as a third electrode can increase catalytic reactions, such as electrochemical reduction of O 2 to H 2 O 2 and its degradation into •OH by direct decomposition and loading of Fe 2+ onto the particle surface. [20][21][22][23] In recent years, researchers have suggested the use of activated carbon, 24 kaolin, 22 nickel foam, 23 bentonite 25 and carbon nanotubes 10 as the supporting material and particle electrode. Amongst these, nickel foam has shown unique properties such as high conductivity, high porosity, high specific surface area and resistance to corrosion giving enhanced mechanical durability and catalytic activity, leading to its use in various fields as catalyst, ion exchanger and supporting material.…”

Degradation of p‐aminophenol wastewater using Ti‐Si‐Sn‐Sb/GAC particle electrodes in a three‐dimensional electrochemical oxidation reactor

“…[15] Compared with the two-dimensional electrochemical oxidation reactor, it has several advantages, including abundant catalytic active sites, high mass transfer efficiency, and greatly improves the removal efficiency of the refractory organic matter. [16,17] Various particle, such as ceramics, [18] γ-Al 2 O 3, [19] kaolin [20] and granular activated carbon (GAC) [21] had been used as the particle electrodes in the electrochemical oxidation reactor. Among these particle electrodes, GAC was widely used for its good electrical conductivity, high specific surface area and low price.…”